Image forming apparatus

Abstract

An image forming apparatus includes a main assembly including an image forming portion, a driving source, and a detection portion, and includes a replacement unit including a rotatable member, a first rotatable member, a second rotatable member, and a pressing member. The detection part changes the state according to the movement of the first rotatable member. The detection mode of the detection signal output by the detection portion differs in a case where the first rotatable member is in a first position and the rotational load torque of the rotatable member is less than a predetermined value, and in a case where the first rotatable member is in a second position and the rotational load torque is less than a predetermined value. And a case where the first rotatable member is in the second position and the rotational load torque is equal to or greater than a predetermined value.

Description

Technical Field

[0001] This disclosure relates to an imaging device that uses an electrophotographic or electrostatic recording type, such as a printer, copier, fax machine, or a multifunction machine having multiple of these functions. Background Technology

[0002] In electrophotographic imaging devices (such as printers), waste toner remaining on the image carrier after the toner image is transferred from the image carrier to the transfer receiving component is removed from the image carrier by a cleaning device and collected in a waste toner collection container. In some cases, the waste toner collection container is equipped with a full-state detection device to prevent waste toner leakage.

[0003] After a full state is detected, the waste toner collection container is replaced by an operator (such as a user or service manager). Furthermore, when the replacement of the waste toner collection container is detected, the full state detection device's detection status is reset, allowing imaging operations to proceed.

[0004] Japanese Patent Application Publication No. (JP-A) 2009-265281 discloses a structure in which the fullness of a waste toner collection container is detected by detecting the rotational load of a stirring member in the container used to agitate the waste toner by rotation. When the installation / removal of the waste toner collection container is detected after it has been found to be full, a countdown is started to determine the number of sheets to be monitored. If fullness is detected again before the count reaches zero, it is determined that the waste toner collection container has not been replaced; conversely, if no fullness is detected, it is determined that the waste toner collection container has been replaced. Therefore, even when the waste toner collection container is merely installed or removed without replacement, the possibility of erroneous detection of waste toner collection container replacement is reduced because fullness is detected again before the count reaches the monitoring count.

[0005] Furthermore, JP-A No. 2019-66597 discloses the following structure: The transfer unit is equipped with a detection rod that assumes different postures between the transfer unit housed in the main equipment assembly and the transfer unit intended for replacement. Furthermore, during the initial operation of the imaging equipment, the system determines whether the transfer unit has been replaced with a new one based on the detection result of the detection rod's posture. Therefore, even if the lifespan of the transfer unit reaches its limit before that of the main equipment assembly, or even if the transfer unit malfunctions, it is possible to detect that the transfer unit has been replaced with a new one, thus allowing continued operation of the main equipment assembly. Summary of the Invention

[0006] According to one aspect of this disclosure, an imaging device is provided, comprising: a main assembly including an imaging unit configured to form an image with a toner, a drive source configured to generate a driving force, and a detection unit capable of taking a first state and a second state and configured to output a detection signal according to each of the first and second states; and a replacement unit detachably mounted to the main assembly and including: a rotatable member; a first rotatable member configured to rotate by inputting a driving force thereto from the drive source; a second rotatable member coaxially disposed with the first rotatable member and configured to rotate by transmitting a driving force thereto from the first rotatable member to transmit a driving force toward the rotatable member; and a pressing member configured to press the first rotatable member against the second rotatable member along the rotation axis of the first rotatable member, wherein the first rotatable member is capable of reacting with the second rotatable member according to the magnitude of the rotational load torque of the rotatable member. The component moves in conjunction with the rotation direction of the first rotatable member relative to the position of the first rotatable member to a first position and a second position. The first position and the second position are different relative to the rotation axis direction of the first rotatable member with respect to the position of the second rotatable member. The detection unit changes its state between a first state and a second state according to the movement of the first rotatable member between the first position and the second position. Furthermore, when the replacement unit is installed in the main assembly, the detection mode of the detection signal output by the detection unit is different in the following cases during a predetermined time period from the start of the drive from the drive source: when the drive source starts, the first rotatable member is in the first position and the rotational load torque of the rotatable member is less than a predetermined value; when the drive source starts, the first rotatable member is in the second position and the rotational load torque of the rotatable member is less than the predetermined value; and when the drive source starts, the first rotatable member is in the second position and the rotational load torque of the rotatable member is greater than or equal to the predetermined value.

[0007] The features of this disclosure will become apparent from the following description of embodiments with reference to the accompanying drawings. The following description of the embodiments is by way of example. Attached Figure Description

[0008] Figure 1 It is a cross-sectional view showing the overall structure of the printer.

[0009] Figure 2 This is a cross-sectional view showing the printer with the door open.

[0010] Figure 3 This is a cross-sectional view of a printer in a state where the fixing unit is in motion.

[0011] Figure 4This is a cross-sectional view of the printer with the transfer unit and tray unit pulled out.

[0012] Figure 5 This is a cross-sectional view of the printer with only the transfer unit pulled out.

[0013] Figure 6 This is a three-dimensional view showing the overall structure of the transfer unit.

[0014] Figure 7 This is a three-dimensional view of the transfer unit, used to show the waste toner delivery path.

[0015] Figure 8 This is a perspective view showing the waste toner delivery path and drive connection mechanism.

[0016] Figure 9 This is a perspective view of the drive connection mechanism in Embodiment 1.

[0017] Figure 10 This is an exploded perspective view of the drive connection mechanism in Embodiment 1.

[0018] Figure 11 Parts (a) to (b) are, respectively, a perspective view and a front view of the movable gear in Example 1. Figure 11 Parts (c) and (d) are, respectively, a perspective view and a front view of the fixed gear in Example 1.

[0019] Figure 12 Parts (a), (b), and (c) are schematic diagrams illustrating the operation of the drive connection mechanism in Embodiment 1.

[0020] Figure 13 Parts (a) and (b) are perspective views used to illustrate the operation of the testing mechanism.

[0021] Figure 14 Parts (a) and (b) are cross-sectional views used to illustrate the operation of the detection mechanism.

[0022] Figure 15 Parts (a) and (b) are time diagrams, which respectively show the detection mode during the detection period when the state is close to full in Example 1.

[0023] Figure 16 This is a flowchart of the detection process when the state is close to full.

[0024] Figure 17 Parts (a) to (c) are schematic diagrams illustrating the operation of the drive connection mechanism during the new product replacement detection in Example 1.

[0025] Figure 18 This is a flowchart of the new product replacement test in Example 1.

[0026] Figure 19 Parts (a) to (c) are time diagrams, which respectively show the detection modes during the new product replacement detection in Example 1.

[0027] Figure 20 Parts (a) and (b) are, respectively, a perspective view and a front view of the movable gear in Example 2. Figure 20 Parts (c) and (d) are, respectively, a perspective view and a front view of the fixed gear in Example 2.

[0028] Figure 21 Parts (a) to (d) are schematic diagrams illustrating the operation of the drive mechanism during the detection of near-full state in Embodiment 2.

[0029] Figure 22 Parts (a) and (b) are perspective views used to illustrate the operation of the testing mechanism.

[0030] Figure 23 Parts (a) and (b) are time diagrams, which respectively show the detection modes during the detection period when the state is close to full in Example 2.

[0031] Figure 24 This is a flowchart of the near-full state detection in Example 2.

[0032] Figure 25 Parts (a) to (c) are schematic diagrams illustrating the operation of the drive connection mechanism during the new product replacement detection in Example 2.

[0033] Figure 26 Parts (a) and (b) are time diagrams, which respectively show the detection modes during the new product replacement detection in Example 2.

[0034] Figure 27 This is a flowchart of the new product replacement test in Example 2.

[0035] Figure 28 This is a block diagram illustrating the schematic control structure of a printer. Detailed Implementation

[0036] The imaging apparatus according to this disclosure will be described in detail below.

[0037] [Example 1]

[0038] <Overall Structure of Imaging Equipment>

[0039] Will use Figure 1 The overall structure of the imaging device in this embodiment is described. Figure 1This is a cross-sectional view showing the overall structure of the imaging device of this embodiment. In this embodiment, the imaging device is a tandem color laser beam printer (hereinafter simply referred to as "printer") 1 of the intermediate transfer type, wherein a full-color image can be formed on the sheet S by using an electrophotographic type.

[0040] Incidentally, regarding printer 1 and its components, Figure 1 The right side of the middle is the "front" side. Figure 1 The left side is the "rear (back)" side. Furthermore, regarding printer 1 and its components, when viewing printer 1 from the front, the left side (… Figure 1 The front of the drawing is the "left" side, and the right side is the "right" side. Figure 1 The "right" side is the back side of the drawing. The left-right direction connecting these left and right sides is generally parallel to the rotation axis of the photosensitive drum 61, which will be described later, and is also generally parallel to the rotation axis of each stretching roller of the intermediate transfer belt 41, which will be described later. Further, in this embodiment, the printer 1 is configured such that the front-back direction and the left-right direction are generally parallel to the horizontal direction H, and is used for imaging. Further, regarding the printer 1 and its components, up and down refer to up and down in the direction of gravity (vertical direction) V, but do not only mean directly above and directly below, but also include the upper and lower sides of the horizontal plane (plane) passing through the position of interest or the element of interest. Further, as the sheet S, paper is usually used, so the sheet S is referred to as paper in some cases, but the sheet S is not limited to paper, and as the sheet S, materials other than paper can also be used, such as plastic sheets, or sheets formed of materials including materials other than paper.

[0041] Printer 1 includes a main assembly (housing) 1a, a scanner 2 (which is an exposure device as an exposure unit), a controller (control circuit) 3 (which is a control device), and a door 20 (which is an openable / closeable member relative to the main assembly 1a). Further, printer 1 includes a sheet feed unit 30, a transfer unit 40 (which is a transfer device (intermediate transfer device) as a transfer unit), a tray unit 50 (which is a moving unit (support unit),) and a fixing device 80 (which is a fixing device). The portion including the main assembly 1a and the door 20 may also be referred to as the main frame 1i. The main frame 1i includes the housing portion of printer 1.

[0042] The main components of the equipment 1a house the scanner 2, controller 3, sheet feed unit 30, transfer unit 40, tray unit 50, and fixing device 80.

[0043] The sheet feed unit 30 includes a stacking tray 31 on which sheets S are stacked, and a feed roller 32 serving as a feed member. The sheets are sheet-like recording materials (transfer materials, recording media, sheets). The stacking tray 31 can be pulled out in the direction from the main equipment assembly 1a to the door 20 (front side). Furthermore, sheets S can be replenished to the stacking tray 31 pulled out from the main equipment assembly 1a.

[0044] The tray unit 50 includes a tray 51 as a support member (drawer) and four cassettes (imaging units) PY, PM, PC, and PK. The tray 51 includes a tray handle 52. Each of the cassettes PY, PM, PC, and PK is detachably (removably) mounted to the tray 51.

[0045] In this embodiment, each of the boxes PY, PM, PC, and PK can be independently and detachably mounted to the tray 51. The four boxes PY, PM, PC, and PK respectively form yellow (Y), magenta (M), cyan (C), and black (K) images (toner images).

[0046] Four cartridges, PY, PM, PC, and PK, respectively contain toners for yellow (Y), magenta (M), cyan (C), and black (K) developers. In this embodiment, a single-component developer is used for each type of developer. Cartridges PY, PM, PC, and PK have substantially the same construction, except that the colors of the toners contained therein differ. For elements having the same or corresponding functions or constructions for the various colors of yellow, magenta, cyan, and black, in some cases these elements are uniformly described by omitting the suffixes Y, M, C, and K in the reference numerals or symbols, where each suffix indicates an element for an associated color. The tray unit 50 can be said to include a plurality of cartridges P and a tray 51 on which the plurality of cartridges P are detachably mounted.

[0047] In this embodiment, the tray unit 50 includes multiple photosensitive drums 61 (61Y, 61M, 61C, 61K), multiple charging rollers 62 (62Y, 62M, 62C, 62K), and multiple developing rollers 71 (71Y, 71M, 71C, 71K). Specifically, the tray unit 50 includes four photosensitive drums 61, four charging rollers 62, and four developing rollers 71. The photosensitive drum 61 is a rotatable drum-shaped (cylindrical) photosensitive component (electrophotographic photosensitive component) serving as a first image-carrying component. The charging rollers 62 are roller-shaped charging components serving as charging devices. The developing rollers 71 are developer-carrying components (developing components) used to carry and deliver toner disposed in a toner-containing component disposed in the tray 51 or cartridge P towards the photosensitive drum 61. The rotation axis directions of the photosensitive drums 61, the developing rollers 71, and the charging rollers 62 are substantially parallel to each other.

[0048] The parts that form the relevant color images (including the photosensitive drum 61, charging roller 62, and developing roller 71) can also be referred to as stations. The black cartridge PK is installed in the black station. The cyan cartridge PC is installed in the cyan station. The magenta cartridge PM is installed in the magenta station. The yellow cartridge PY is installed in the yellow station.

[0049] The photosensitive drum 61, charging roller 62, and developing roller 71 only need to be housed in either the cartridge P or the tray 51. In this embodiment, the cartridge P includes the photosensitive drum 61, charging roller 62, and developing roller 71. Incidentally, the tray unit 50 may include a drum cleaning section (drum cleaning device) as a photosensitive component cleaning device for removing toner from an associated photosensitive drum 61. That is, the tray unit 50 may include multiple drum cleaning sections for cleaning the surfaces of each photosensitive drum 61. The drum cleaning sections may be housed in either the cartridge P or the tray 51. For example, the drum cleaning section scrapes the toner from the surface of the rotating photosensitive drum 61 by a cleaning scraper (as a cleaning component) that contacts the surface of the photosensitive drum 61, and collects the toner in a toner collection section provided in the tray 51 or the cartridge P.

[0050] The transfer unit 40 includes an intermediate transfer belt (hereinafter simply referred to as "belt") 41, primary transfer rollers 42 (42Y, 42M, 42C, 42K), a cleaning section 43, a drive roller 46, and a tension roller (driven roller, follower roller) 47. The belt 41 is an intermediate transfer member consisting of an annular belt that serves as a second image carrier. The primary transfer roller 42 is a roller-type primary transfer member that serves as a primary transfer device. The cleaning section (belt cleaning device) 43 is a cleaning device for cleaning the surface of the belt 41. The drive roller 46 and the tension roller 47 are stretching rollers for stretching the belt 41. The drive roller 46 drives the belt 41. Furthermore, the tension roller 47 applies a predetermined tension to the belt 41. Through the drive roller 46 and the tension roller 47, a primary transfer surface 41a is formed on which the toner image is transferred from the photosensitive drums 61Y, 61M, 61C, and 61K, and this primary transfer surface is the surface of the belt 41.

[0051] In this embodiment, printer 1 includes an optical sensor 44 for detecting the toner image transferred onto the belt 41. In this embodiment, the belt 41 is disposed below the photosensitive drums 61Y, 61M, 61C, and 61K. The belt 41 can contact the photosensitive drum 61, thereby forming a primary transfer section between the belt 41 and the photosensitive drum 61. Further, printer 1 includes a secondary transfer roller 45 at a location where it faces the drive roller 46 across the belt 41. The secondary transfer roller 45 contacts the belt 41, thereby forming a secondary transfer section between the belt 41 and the secondary transfer roller 45. The rotation axis directions of the primary transfer roller 42, the drive roller 46, the tension roller 47, and the secondary transfer roller 45 are substantially parallel to each other. An alignment roller pair 4, serving as a synchronous transport member, is provided on the front side of the secondary transfer section relative to the conveying direction of the sheet S.

[0052] The fixing device 80 includes a fixing section 81 and a baffle 5. When performing an imaging operation to form an image on the sheet S, the fixing device 80 is in the use position. In the use position, the fixing device 80 is housed within the inner portion (inner side) of the main assembly 1a. Furthermore, the fixing device 80 is configured to heat the sheet S when in the use position. In this embodiment, the fixing section 81 includes a heating section (heating roller) containing a heater, and a pressure section (pressure roller) for clamping and conveying the sheet S in cooperation with the heating section.

[0053] Will use Figures 1 to 5 The movement of the transfer unit 40 and the tray unit 50 is described. Figure 2 This is a cross-sectional view showing printer 1 with door 20 open. Figure 3 This is a cross-sectional view of the printer 1 with the fixing device 80 in a moved state. Figure 4 This is a cross-sectional view of the printer 1 with the transfer unit 40 and tray unit 50 pulled out from the main assembly 1a of the device. Figure 5 This is a cross-sectional view of the printer 1 with the transfer unit 40 pulled out separately from the main device assembly 1a.

[0054] The transfer unit 40 and the tray unit 50 are movable from the inside to the outside of the main assembly 1a. Relative to the horizontal direction H (front-back direction), the main assembly 1a includes a first end 1b1 with a main assembly opening 1a1 (which is an opening), and a second end 1b2 located on the opposite side of the first end 1b1. The tray unit 50 can move through the main assembly opening 1a1 between a first inner position inside the main assembly 1a and a first outer position outside the main assembly 1a. The transfer unit 40 can move through the main assembly opening 1a1 between a second inner position inside the main assembly 1a and a second outer position outside the main assembly 1a. The main assembly opening 1a1 can also be configured to include an opening through which the tray unit 50 passes and an opening through which the transfer unit 40 passes. Incidentally, when the transfer unit 40 moves from the second inner position to the second outer position, at least the tape 41 is moved, and at least a portion of the tape 41 protrudes from the main assembly 1a toward the outside of the main assembly 1a.

[0055] The direction in which tray unit 50 moves from the first inner position to the first outer position is called the tray removal direction Dd1, and the direction opposite to tray removal direction Dd1 is called the tray mounting (attachment) direction Da1. In other words, tray removal direction Dd1 is the direction from the second end 1b2 towards the first end 1b1. The direction in which transfer unit 40 moves from the second inner position to the second outer position is called the transfer (unit) removal direction Dd2, and the direction opposite to transfer removal direction Dd2 is called the transfer (unit) mounting (attachment) direction Da2. The drive roller 46 is positioned downstream of the tension roller 47 relative to the transfer removal direction Dd2. In other words, transfer removal direction Dd2 is the direction from the second end 1b2 towards the first end 1b1. Each of the tray removal direction Dd1 and tray mounting direction Da1 is a direction that intersects (preferably is substantially perpendicular) to the rotation axis direction of the photosensitive drum 61. Each of the transfer removal direction Dd2 and transfer mounting direction Da2 is a direction that intersects (preferably is substantially perpendicular) to the rotation axis direction of the drive roller 46. The rotation axis of the drive roller 46 is approximately parallel to the rotation axis of the photosensitive drum 61. In the horizontal direction H (front-back direction), a fixing device 80 is arranged on one end side of the main assembly 1a of the device (on the side where the first end 1b1 is provided).

[0056] The door 20, which is installed on the main component 1a of the device, can move between a closed position and an open position.

[0057] like Figure 1 As shown, when door 20 is in the closed position (door 20 closed state), door 20 covers the main component opening 1a1. Figure 2 As shown, when the door 20 is in the open position (the open state of the door 20), the main component opening 1a1 is exposed.

[0058] like Figure 1 As shown, when the door 20 is in the closed position, the door 20 covers the fuser unit 80 mounted to the main assembly 1a of the device. Specifically, when the door 20 is in the closed position, the upper cover 20b of the door 20 is positioned above the fuser unit 80. The upper cover 20b of the door 20 functions as part of the housing of the printer 1.

[0059] With the fixing unit 80 supported by the main equipment assembly 1a, the door 20 can move to an open position and a closed position. In other words, the door 20 moves from the closed position to the open position to separate from the fixing unit 80 supported by the main equipment assembly 1a. Therefore, as Figure 2 As shown, when the door 20 is in the open position, the door 20 is separated from the fixing device 80 supported by the main equipment assembly 1a.

[0060] As described above, the fixing device 80 can be from Figure 2 The state shown moves to Figure 3 The state shown is such that the main component opening 1a1 is fully exposed. Figure 3 As shown, with the door 20 and fixing device 80 moved, the transfer unit 40 and tray unit 50 can move from the inside to the outside of the main assembly 1a through the main assembly opening 1a1, and after the movement, they become... Figure 4 The state shown in the image.

[0061] like Figure 4 As shown, with the tray unit 50 moved outside the main assembly 1a, it is permissible to remove each of cartridges PY, PM, PC, and PK from the tray 51 and to install each of cartridges PY, PM, PC, and PK onto the tray 51. Thus, cartridges PY, PM, PC, and PK can be replaced with new cartridges PY, PM, PC, and PK, respectively. In this embodiment, cartridge P can be detachably installed onto the tray 51 with respect to a direction intersecting (preferably substantially perpendicular) to the rotation axis of the photosensitive drum 61.

[0062] Each of the boxes PY, PM, PC, and PK is removed from the tray 51 by being moved relative to the tray 51 in a direction away from the transfer unit 40. In other words, each of the boxes PY, PM, PC, and PK is removed from the tray 51 by being moved relative to the tray 51 toward the side opposite to the transfer unit 40. In this embodiment, the transfer unit 40 is disposed below the tray unit 50. Therefore, each of the boxes PY, PM, PC, and PK is removed from the tray 51 by being moved upward relative to the tray 51.

[0063] Furthermore, such as Figure 5As shown, the transfer unit 40 can be detached from the main equipment assembly 1a independently of the tray unit 50. Therefore, the transfer unit 40 can be replaced with a new transfer unit 40.

[0064] <Imaging Operation>

[0065] Will use Figure 1 The imaging operation of printer 1 is described. The controller 3 of printer 1 initiates an imaging operation to form an image on sheet S based on image information (image signal) received from an external host device 400. The external host device 400 is, for example, a personal computer, an image reader, a fax machine, etc.

[0066] When the imaging operation is performed, the fixing device 80 is positioned in the use position, the tray unit 50 is positioned in the first inner position, the transfer unit 40 is positioned in the second inner position, and the door 20 is positioned in the closed position. With the transfer unit 40 in the second inner position, the belt 41 can contact the photosensitive drums 61Y, 61M, 61C, and 61K. At this time, the tray unit 50 is positioned above the transfer unit 40.

[0067] When imaging operation begins, the photosensitive drum 61 is driven to rotate, and a charging voltage is applied to the charging roller 62. The photosensitive drum 61 is driven to rotate along... Figure 1 The belt is driven to rotate clockwise. Furthermore, the belt 41 is driven to rotate. This is achieved by the drive motor 5 ( Figure 28 The drive roller 46 rotates along the belt 41. Figure 1 The photosensitive drum 61 rotates counterclockwise (circulates and moves). The surface of the photosensitive drum 61 is uniformly charged by the charging roller 62 to a predetermined polarity (negative polarity in this embodiment) and a predetermined potential. The charged surface of the photosensitive drum 61 is irradiated by a laser corresponding to the image information from the scanner 2, thus exposing the surface of the photosensitive drum 61 to the laser. As a result, an electrostatic latent image (electrostatic image) corresponding to the image information is formed on the surface of the photosensitive drum 61.

[0068] In this embodiment, the developing roller 71 carries the toner disposed in the toner accommodating portion in the cartridge P. A developing voltage is applied to the developing roller 71, thereby supplying the toner from the developing roller 71 to the surface of the photosensitive drum 61 according to the electrostatic latent image formed on the surface of the photosensitive drum 61.

[0069] Thus, the electrostatic latent image on the surface of the photosensitive drum 61 is developed (visualized), thereby forming a toner image (toner picture, developer image) on the surface of the photosensitive drum 61. In this embodiment, toner charged to the same polarity (negative polarity in this embodiment) as the charge polarity of the photosensitive drum 61 is deposited on the exposed portion of the photosensitive drum 61, where the absolute value of the charge decreases due to the surface of the photosensitive drum 61 being exposed to laser light after being uniformly charged. In this embodiment, the normal charge polarity of the toner (which is the dominant charge polarity of the toner during development) is negative. In this embodiment, the developing roller 71 develops the electrostatic latent image while in contact with the photosensitive drum 61.

[0070] However, the printer 1 may have a configuration in which the developing roller 71 develops an electrostatic latent image while there is a gap between the developing roller 71 and the photosensitive drum 61.

[0071] For example, during panchromatic imaging, toner images in yellow, magenta, cyan, and black are formed on photosensitive drums 61Y, 61M, 61C, and 61K, respectively.

[0072] Incidentally, in this embodiment, when the tray unit 50 is in the first inner position, the developing roller 71 can move between a contact position where the developing roller 71 contacts the photosensitive drum 61 and a separation position where the developing roller 71 is separated from the photosensitive drum 61. Specifically, the state in which the developing roller 71 is in the contact position and the state in which the developing roller 71 is in the separation position are switched by a switching device (not shown) provided in the main assembly 1a of the device. Thus, when no imaging operation is performed, the developing roller 71 can remain separated from the photosensitive drum 61.

[0073] Furthermore, printer 1 can perform monochrome printing (printing) with the developing roller 71 of cartridge PK in contact with the photosensitive drum 61, while the developing roller 71 of each of cartridges PY, PM, and PC is separated from the photosensitive drum 61. Furthermore, printer 1 can perform full-color printing (printing) with the photosensitive drum 61 of cartridges PY, PM, PC, and PK in contact with the belt 41.

[0074] The toner image formed on the photosensitive drum 61 is transferred (primarily transferred) in the primary transfer section to the rotating belt 41, which serves as a transfer receiving member, by the action of the primary transfer roller 42. During the primary transfer, a primary transfer voltage is applied to the primary transfer roller 42, the polarity of which is opposite to the normal charge polarity of the toner. By rotating the belt 41, the toner image transferred on the belt 41 is conveyed toward the secondary transfer section formed by the belt 41 and the secondary transfer roller 45. For example, during panchromatic imaging, toner images of yellow, magenta, cyan, and black formed on the photosensitive drums 61Y, 61M, 61C, and 61K are successively superimposed and transferred to the same imaging area on the belt 41.

[0075] On the other hand, in the main assembly 1a, a transport path (first path, first transport path) 1c is formed, along which the sheet S guided toward the fixing unit 80 passes. Furthermore, a double-sided transport path (second path, second transport path) 20a is formed on the door 20, along which the sheet S moving toward the fixing unit 80 passes. The door 20 covers the transport path 1c when closed. Figure 2 As shown, door 20 is opened, thus exposing transport path 1c and double-sided transport path 20a. In the sheet feeding section 30, at a predetermined time, a sheet S is separated from and fed from the stacked pallet 31 by the feed roller 32. The sheet S passes through the transport path 1c and is transported toward the secondary transfer section and fixing device 80. That is, the sheet S fed from the stacked pallet 31 by the feed roller 32 is transported to the alignment roller pair 4. The sheet 4 is transported toward the secondary transfer section by the alignment roller pair 4 in sync with the toner image on the belt 41.

[0076] The toner image formed on the belt 41 is transferred (secondary transfer) in the secondary transfer section onto the sheet S held and conveyed by the belt 41 and the secondary transfer roller 45 by the action of the secondary transfer roller 45. During the secondary transfer, a secondary transfer voltage is applied to the secondary transfer roller 45, the polarity of which is opposite to the normal charge polarity of the toner. Toner remaining on the belt 41 and not transferred to the sheet S (waste toner, residual toner) is removed from the belt 41 and collected by the cleaning section 43. The cleaning section 43 includes a cleaning scraper 43a (as a cleaning member) that contacts the surface of the belt 41, and a cleaning container 43b that forms a toner collection area. The cleaning scraper 43a is disposed in the cleaning container 43b. The cleaning section 43 scrapes the toner from the surface of the rotating belt 41 by the cleaning scraper 43a and collects the toner in the cleaning container 43b. The toner removed from the surface of belt 41 by cleaning section 43 passes from cleaning section 43 toward waste toner collection container 10, which will be described later. Figure 7 It is transported and collected (accumulated) as residual (waste) toner.

[0077] In the secondary transfer section, the sheet S with the toner image transferred is conveyed toward the fixing device 80. The fixing section 81 of the fixing device 80 heats and pressurizes the sheet S, which carries the unfixed toner image, and fixes (melts, adheres) the toner image onto the sheet S. The sheet S with the fixed toner image is then conveyed toward the baffle 5, which serves as a path switching section.

[0078] The baffle 5 is movable to the discharge position and the reversing roller. In the discharge position, the sheet S passing through the fixing device 80 is guided toward the discharge path 1d, and at the reversing roller, the sheet S is guided toward the reversing path 1e. In the case of single-sided printing (printing) where an image is formed on one surface (side) of the sheet S, the sheet S is guided by the baffle 5 to the discharge path 1d and discharged (output) to the discharge tray 1f formed on the upper part of the main assembly 1a of the device. On the other hand, in the case of double-sided printing (printing) where an image is formed on the first surface (side) (front surface (side)) and the second surface (side) (rear surface (side)) of the sheet S, the sheet S with the toner image fixed on the first surface is guided by the baffle 5 to the reversing path 1e. After being guided to the reversing path 1e, the sheet S is reversed in its transport direction. Then, the sheet S passes through the double-sided transport path 20a formed on the gate 20 and is transported toward the secondary transfer section, where the toner image is transferred onto the second surface. Subsequently, the sheet S passes through the fixing device 80 and is guided by the baffle 5 to the discharge path 1d, and is then discharged to the discharge tray 1f of the main assembly 1a of the device.

[0079] In this embodiment, the imaging unit 1h for forming a toner image on the sheet S is composed of imaging units P, a transfer unit 40, a secondary transfer roller 45, etc. Furthermore, in this embodiment, the cleaning unit 43 of the belt 41 is an example of a cleaning unit for collecting toner from the imaging unit 1h. Furthermore, in this embodiment, the waste toner collection container 10 (described later) for containing toner collected from the belt 41... Figure 7 This is an example of a waste toner collection container 10 for containing toner collected by the cleaning department (waste toner collected in the main components of the equipment).

[0080] <Control Structure>

[0081] Figure 28This is a block diagram illustrating the schematic control structure of printer 1. Printer 1 includes a controller 3, which serves as a control device for overall control of printer 1. The controller 3 is configured by including: a CPU 3a as an arithmetic processing unit (arithmetic processing section), a memory 3b as a storage device (storage section), and input / output circuitry (not shown) as an input / output device (input / output section). The memory 3b is configured by including ROM, RAM, and EEPROM. The ROM stores the control program and application program executed by the CPU 3a. The RAM serves as a working area for executing the control program. The EEPROM stores data that should be saved even when the power to printer 1 is turned off, such as various settings. The CPU 3a executes control of printer 1 according to the program stored in the memory 3b (ROM).

[0082] For example, the detection mechanism 100, operation unit 4, drive motor 5, scanner 2, high-voltage power supply 6, etc., described later, are connected to the controller 3. As described later, the detection mechanism is able to detect the movement of the movable gear 121 in the drive transmission mechanism 120 in the direction of the rotation axis, which drives the waste toner delivery screw 113 provided in the waste toner collection container 10. Furthermore, the detection mechanism 100 is able to detect that the rotational load torque of the waste toner delivery screw 113 becomes above a predetermined value (overload state), as described later. The detection mechanism 100 inputs a signal indicating its detection result to the controller 3. The operation unit 4 is configured by including a display unit for displaying information to the user (operator) under the control of the controller 3, and an input unit for inputting information such as various settings to the controller 3 based on the user's operation. The operation unit 4 can be configured by including a touch panel with the functions of a display unit and an input unit. In this case, the operation unit 4 performs screen display to the user and receives the user's touch input. The drive motor 5 is a drive source for generating driving force to rotate the belt 41 (drive roller 46). Incidentally, the printer 1 may also be provided with another drive motor as a drive source for another driven part (such as the photosensitive drum 61 or the fuser 80). Furthermore, at least a portion of the drive source for the drive roller 46 (as a driven part) and the drive source for another driven part (such as the photosensitive drum 61 or the fuser 80) may be shared. A high-voltage power supply 6 applies a predetermined voltage to the charging roller 62, the developing roller 71, the primary transfer roller 42, the secondary transfer roller 45, etc. A separate high-voltage power supply 6 may be provided for each application target, and the high-voltage power supply 6 for multiple application targets may also be shared. Furthermore, the external host device 400 is connected to the controller 3. The controller 3 is capable of controlling various parts of the printer 1 to perform imaging operations based on print commands or image information input from the external host device 400. Furthermore, the controller 3 is capable of performing detection and notification processing for the waste toner collection container 10 to be near full or full, as well as detection processing for the replacement of new waste toner collection container 10 (transfer unit 40), as described later.

[0083] <Residual Toner Delivery Path>

[0084] Will use Figures 6 to 8 Describe the waste toner transport path. Figure 6 This is a perspective view showing the overall structure of the transfer unit 40 in this embodiment. Figure 7 This is a perspective view of the transfer unit 40, used to show the waste toner delivery path in this embodiment, showing the state in which the belt 41, the cleaning container 43b of the cleaning section 43, etc. are removed from the transfer unit 40.

[0085] Figure 8 This is a perspective view showing the waste toner delivery path and drive connection mechanism in this embodiment.

[0086] The cleaning unit 43 includes a cleaning container 43b and a cleaning scraper 43a disposed inside the cleaning container 43b. The cleaning scraper 43a extends along the width direction (left-right direction), which is substantially perpendicular to the surface movement direction of the belt 41. The cleaning scraper 43a is configured to contact the drive roller 46 across the belt 41. Furthermore, the cleaning scraper 43a is configured to contact the surface (outer peripheral surface) of the belt 41 in a direction opposite to the movement direction of the belt 41. That is, the cleaning scraper 43a contacts the surface of the belt 41 in such an orientation that the free end of the cleaning scraper relative to the width (short side) direction points upstream of the surface movement direction of the belt 41, which is substantially perpendicular to the longitudinal direction set along the width direction of the belt 41. The cleaning scraper 43a scrapes away the toner from the surface of the rotating belt 41 and contains the toner as waste toner in the cleaning container 43b. Here, the cleaning scraper 43a contacts the belt 41 at a predetermined angle, allowing the toner to be removed from the surface of the belt 41 by movement of the belt 41 in one direction. In this embodiment, no driving force is input from the drive source to the drive roller 46 to cause the belt 41 and the drive roller 46 to rotate in opposite directions.

[0087] The transfer unit 40 includes a transfer frame 48, which serves as a frame for supporting the drive roller 46, tension roller 47, primary transfer roller 42, etc. In this embodiment, a space (area) for accommodating waste toner is provided inside the transfer frame 48. That is, in this embodiment, the transfer frame 48 can also be considered as a waste toner collection container 10. However, the waste toner collection container 10 can also be constructed separately from the transfer frame 48 and can be installed to the transfer frame 48. That is, in this embodiment, the waste toner collection container 10 is disposed in the area formed by the inner peripheral surface of the belt 41. In this embodiment, in the main assembly 1a of the device, the waste toner collection container 10 is configured such that its bottom intersects the direction of gravity. Further, in this embodiment, when the waste toner collection container 10 is viewed in a direction substantially perpendicular to the primary transfer surface 41a of the belt 41, the waste toner collection container 10 is constructed in a substantially rectangular shape. In a portion of the upper surface of the waste toner collection container 10 opposite to the primary transfer rollers 42Y, 42M, 42C, and 42K, grooves 10bY, 10bM, 10bC, and 10bK are formed respectively along the rotation axis direction (left-right direction) of each primary transfer roller 42. Thus, the waste toner collection container 10 does not restrict the rotation of each primary transfer roller 42. The drive roller 46, tension roller 47, and each primary transfer roller 42 are rotatably supported by a support portion provided on the transfer frame 48.

[0088] The cleaning section 43 includes a cleaning screw 111 and an intermediate screw 112, which are waste toner conveying components for conveying waste toner removed from the belt 41 by the cleaning scraper 43a. The cleaning screw 111 includes a rotating shaft arranged along the width direction (left-right direction) of the belt 41 and a spiral conveying section formed along the axial direction of the rotating shaft. The cleaning screw 111 is driven to a drive roller 46 via a drive connection (not shown) and rotates by receiving a driving force input from the drive motor 5 to the drive roller 46. Furthermore, the cleaning screw 111 rotates along... Figure 8 The waste toner is conveyed in the direction of arrow Ta (from right to left). The intermediate screw 112 includes a rotating shaft arranged in a direction intersecting the rotation axis of the cleaning screw 111 (intersecting the horizontal direction), and a helical conveying section formed along the axial direction of the rotating shaft. One end (upper end) of the intermediate screw 112 relative to the rotation axis is positioned close to one end (left end) of the cleaning screw 111 relative to the rotation axis. The intermediate screw 112 is driven to the cleaning screw 111 at this end and rotates by receiving driving force from the cleaning screw 111. Furthermore, the intermediate screw 112 is rotated along... Figure 8 Waste toner is conveyed in the direction of arrow Tb (from top to bottom). The other end of the intermediate screw 112 relative to the axis of rotation is positioned close to one end of the waste toner conveying screw 113 (described later) relative to the axis of rotation (the end located on the left and front sides). The intermediate screw 112 is positioned in the conveying path 43b1 (… Figure 6 The conveying path is located inside the left end of the cleaning container 43b. This conveying path 43b1 is connected to the inlet port 10a of the waste toner collection container 10. Figure 8 And through the inlet port 10a, the interior of the waste toner collection container 10 and the interior of the conveying path 43b1 are connected to each other. The cleaning screw 111 along... Figure 8 The waste toner, conveyed in the direction of arrow Ta, is fed by the intermediate screw 112 along... Figure 8 The waste toner is conveyed in the direction of arrow Tb, so that it flows into the waste toner collection container 10 through the inlet port 10a.

[0089] Furthermore, a waste toner conveying screw 113, serving as a waste toner conveying member, is provided inside the waste toner collection container 10. The waste toner conveying screw 113 includes a rotating shaft and a helical conveying section formed along the axial direction of the rotating shaft. One end of the waste toner conveying screw 113 relative to the rotation axis (the end located on the left and front sides) is positioned close to the inlet port 10a of the waste toner collection container 10. The other end of the waste toner conveying screw 113 relative to the rotation axis is rotatably supported by a bearing portion 10c provided inside the waste toner collection container 10. The waste toner conveying screw 113 is driven to the drive roller 46 via a drive connection mechanism 120, described later, and rotates by receiving a driving force input from the drive motor 5 to the drive roller 46 via the drive connection mechanism 120. Then, through rotation, the waste toner conveying screw 113 moves along... Figure 8 The waste toner is conveyed in the direction of arrow Tc through inlet port 10a into the waste toner collection container 10.

[0090] When the waste toner conveying screw 113 is viewed in a direction substantially perpendicular to the primary transfer surface 41a of the belt 41, the direction of the rotation axis of the waste toner conveying screw 113 is not perpendicular to the movement direction (front-back direction) of the primary transfer surface 41a and the width direction (left-right direction) of the belt 41, but intersects these directions. When the waste toner collection container 10 is viewed in a direction substantially perpendicular to the primary transfer surface 41a of the belt 41, as... Figure 8 As indicated by arrow Tc, waste toner flowing into the waste toner collection container 10 through inlet port 10a is conveyed by the waste toner conveying screw 113 toward the approximate center of the waste toner collection container 10. The end of the helical conveying section of the waste toner conveying screw 113, located on the side opposite to inlet port 10a in the direction of the rotation axis of the waste toner conveying screw 113, is positioned at the approximate center of the waste toner collection container 10. Therefore, the waste toner conveyed by the waste toner conveying screw 113 gradually fills the waste toner collection container 10 while spreading outwards in a concentric circle shape from the approximate center of the container.

[0091] Therefore, the toner removed from the belt 41 by the cleaning scraper 43a is conveyed toward the waste toner collection container 10 via the cleaning screw 111 located inside the cleaning container 43b and the intermediate screw 112. Furthermore, the waste toner collection container 10 is provided with a waste toner conveying screw 113 for conveying waste toner toward the approximate center of the waste toner collection container 10, and waste toner accumulates within the waste toner collection container 10. The waste toner conveying screw 113, as a driven component, is rotated by input driving force from the drive motor 5, which serves as the drive source, via the drive connection mechanism 120 described later. Furthermore, as the amount of waste toner increases due to an increase in the number of sheets printed by the printer 1, the waste toner is conveyed radially outward from the center of the waste toner collection container 10.

[0092] In this embodiment, when the amount of waste toner accumulated in the waste toner collection container 10 reaches or exceeds a predetermined amount (typically, when the amount of waste toner exceeds a predetermined amount), this state is detected, and a warning about this state is issued to the user. In this embodiment, this state is referred to as a "nearly full state," and the warning issued to the user when the amount of waste toner reaches this state is referred to as a "nearly full state notification." In this embodiment, even after the near full state notification is issued, the printer 1 can continue printing until the amount of waste toner collected in the waste toner collection container 10 reaches a predetermined amount (a second predetermined amount). Then, when the amount of waste toner collected in the waste toner collection container 10 reaches a predetermined amount (a second predetermined amount) that waste toner can accumulate in the waste toner collection container 10, this state is detected, and a warning about this state is issued to the user. In this embodiment, this state is referred to as a "full state," and the warning issued to the user when the amount of waste toner reaches this state is referred to as a "full state notification." In this embodiment, when a full state notification is issued, the operation of the printer 1 is stopped (printing operation is prohibited).

[0093] As the amount of waste toner in the waste toner collection container 10 increases, the density of the waste toner becomes higher. Consequently, the resistance generated when the waste toner is conveyed by the waste toner conveying screw 113 increases, resulting in an increase in the rotational load torque of the waste toner conveying screw 113.

[0094] In this embodiment, when the rotational load torque of the waste toner conveying screw 113 reaches a predetermined value or higher (overload state) (typically, when the rotational load torque exceeds the predetermined value), the near-full state of the waste toner collection container 10 is detected by the detection mechanism 100, which will be described later. Figure 13The detector 100 detects the problem. Based on the detection results, the controller 3 notifies the user of a warning by displaying the warning on the screen of the operation unit 4 of the printer 1. This warning can be displayed by showing a message urging the user to prepare to replace the waste toner collection container 10. Alternatively, a similar warning can be displayed on a display unit of an external host device 400 connected to the printer 1, or in addition to the operation unit 4.

[0095] Furthermore, in this embodiment, even after detecting that the waste toner collection container 10 is nearly full, the printing operation can continue until the amount of waste toner collected in the waste toner collection container 10 reaches a predetermined amount and becomes full. In this embodiment, the controller calculates the amount of toner consumed during the printing operation from the near-full state to the full state based on image information. That is, the amount of toner consumed by the printing operation can be calculated by counting the number of pixels in the printed image. Then, when the amount of toner consumed by the printing operation reaches a predetermined amount from the detection of the near-full state, the controller 3 notifies the user of a warning by displaying it on the screen of the operation unit 4 provided on the printer 1. This warning can be implemented by displaying a message urging the replacement of the waste toner collection container 10. However, the means for detecting the amount of waste toner collected in the waste toner collection container 10 after detecting the near-full state are not limited to the above method. For example, the following methods can be used, wherein: the number of sheets that have undergone printing is counted; a detection device for detecting the full state is provided; and the rotation time or number of rotations of the drive roller 46 (transfer unit 40) is counted. Furthermore, instead of the operation unit 4, or in addition to the operation unit 4, similar warnings can be displayed in a display unit or the like on an external host device 400 connected to the printer.

[0096] <Drive Connection Mechanism>

[0097] Will use Figures 8 to 10 The drive connection mechanism 120, which serves as a drive connection device (drive connection part) in this embodiment, is described. This drive connection mechanism is used to transmit drive force from the drive motor 5 to the waste toner delivery screw 113. Figure 9 This is a perspective view of the drive connection mechanism 120 in this embodiment. Figure 10 This is an exploded perspective view of the drive connection mechanism 120 in this embodiment.

[0098] like Figure 8 As shown, the waste toner conveying screw 113 and the drive roller 46 are driven connected to each other via a drive connection mechanism 120 provided in the transfer unit 40. The drive connection mechanism 120 is located at the left end of the drive roller 46 in the direction relative to the rotation axis of the drive roller 46. Figure 9 and Figure 10 As shown, the drive connection mechanism 120 is composed of a movable gear 121, a fixed gear 122, a detection rod 123, a push spring 124, a cover member 125, a drive gear 126, and an idler gear 127.

[0099] The movable gear 121 is a drive transmission member for receiving drive force from the drive roller 46 side and is movably arranged along its rotational axis. As described later, the movable gear 121 can move to a first position and a second position in conjunction with the change in the relative position of the fixed gear 122 with respect to the rotational direction relative to the movable gear 121, depending on the magnitude of the rotational load torque of the waste toner conveying screw 113. The fixed gear 122 is a drive transmission member for receiving drive force from the movable gear 121 by engaging with it, and for transmitting drive force to the waste toner conveying screw 113 by engaging with the waste toner conveying screw gear 113a disposed on the waste toner conveying screw 113. The waste toner delivery screw gear 113a is disposed in one end (the left and front ends) of the waste toner delivery screw 113 relative to the axis of rotation, and rotates integrally with the waste toner delivery screw 113. The detection rod 123 is a detection member used to detect the movement of the movable gear 121 by moving integrally with it. The detection rod 123 includes a rod portion 123a and a rod support portion 123b, and the rod support portion 123b engages in a movable gear recess 121f provided in the movable gear 121. Thus, the detection rod 123 is rotatably held relative to the movable gear 121 to maintain the position of the rod portion 123a relative to the rotational direction of the movable gear 121. The push spring 124 is a push member (compression coil spring, which is an elastic member in this embodiment) that acts as a pusher device, used to push the movable gear 121 toward the fixed gear 122 along the rotation axis direction of the movable gear 121 via the detection rod 123. The cover member 125 is a retaining member that functions to hold the drive connection mechanism 120 to the transfer frame 48 and is fixed to the transfer frame 48. The drive gear 126 is disposed in one end of the drive roller 46 relative to the rotation axis direction (the end located on the left side) to the rotation axis 46a of the drive roller 46 so as to rotate integrally with the drive roller 46. The idler gear 127 receives the driving force from the drive gear 126 by engaging with the drive gear 126 and transmits the driving force to the movable gear 121. That is, the drive gear 126 transmits the drive to the movable gear 121 via the idler gear 127. For example, driving force is input from the drive motor 5 toward the drive roller 46 via a drive connection (not shown) located at the other end of the drive roller 46 relative to the direction of the rotation axis (the end located on the right).

[0100] Here, the surface of the fixed gear 122, located on the side opposite to the movable gear 121 relative to the axis of rotation, abuts against the wall surface of the transfer frame 48. A push spring 124 is disposed between the cover member 125 (whose position is fixed) and the detection rod 123, which can move along the axis of rotation of the movable gear 121. Furthermore, the movable gear 121 and the detection rod 123 are pushed towards the fixed gear 122 by the push spring 124 along the axis of rotation of the movable gear 121. That is, the movable gear 121 and the detection rod 123 are disposed between the fixed gear 122 and the cover member 125 with a certain degree of freedom, so that the movable gear 121 and the detection rod 123 can move along the axis of rotation of the movable gear 121.

[0101] Therefore, the drive connection mechanism 120 includes: a movable gear 121 as a first rotatable member (first member, rotatable member), which is disposed on the input side of the rotational driving force; a fixed gear 122 as a second rotatable member (second member, rotated member), which is coaxially disposed with the first rotatable member and rotatably disposed relative to the first rotatable member and disposed on the output side of the rotational driving force; a push spring 124 as a push member (elastic member), which is used to apply a pushing force (elastic force) in the direction in which the movable gear 121 is pushed against the fixed gear 122 along the rotation axis; and a detection rod 123, which can move together with the movable gear 121.

[0102] Figure 11 Parts (a) and (b), and parts (c) and (d) are perspective views and front views, respectively, which specifically show the movable gear 121 and the fixed gear 122 in this embodiment. Figure 11 Part (a) is a perspective view showing the surface of the movable gear 121 located on the side of the fixed gear 122 in the direction of the rotation axis of the movable gear 121. Figure 11 Part (b) is a front view showing the surface of the movable gear 121. Figure 11 Part (c) is a perspective view showing the surface of the fixed gear 122 located on the side of the movable gear 121 in the direction of the rotation axis of the fixed gear 122. Figure 11 Part (d) is a front view showing the surface of the fixed gear 122.

[0103] The movable gear 121 and the fixed gear 122 include cam shapes (cam shape portions) that can engage with each other.

[0104] exist Figure 11In portions (a) and (b), the movable gear 121 rotates in the direction of arrow R1. The movable gear 121 includes a cam shape along the direction of rotation (circumferential direction). The movable gear 121 includes a first inclined surface portion 121a, a flat surface portion 121b, a first vertical wall portion 121c, a second vertical wall portion 121d, and a second inclined surface portion 121e. In the first inclined surface portion 121a and the second inclined surface portion 121e, the first inclined surface portion 121a is disposed downstream of the movable gear 121 with respect to the direction of rotation, and the second inclined surface portion 121e is disposed upstream of the movable gear 121 with respect to the direction of rotation. The first inclined surface portion 121a is inclined with respect to the axis of rotation of the movable gear 121 so as to approach the fixed gear 122 towards the upstream side of the movable gear 121 with respect to the direction of rotation. Furthermore, the second inclined surface portion 121e is inclined relative to the rotation axis direction of the movable gear 121, so as to separate from the fixed gear 122 as it moves upstream of the movable gear 121 relative to the rotation direction. Furthermore, on the surface of the base portion 121g, where the first inclined surface portion 121a and the second inclined surface portion 121e are formed, located on the side of the fixed gear 122, a protruding shape portion including a first vertical wall portion 121c, a second vertical wall portion 121d, and a flat surface portion 121b is provided. Each of the first vertical wall portion 121c and the second vertical wall portion 121d extends along (in this embodiment, substantially parallel to) the rotation axis direction of the movable gear 121. Of the first vertical wall portion 121c and the second vertical wall portion 121d, the first vertical wall portion 121c is disposed downstream of the movable gear 121 relative to the rotation direction, and the second vertical wall portion 121d is disposed upstream of the movable gear 121 relative to the rotation direction. The flat surface portion 121b extends between the first vertical wall portion 121c and the second vertical wall portion 121d along the direction of the movable gear 121 that intersects (in this embodiment, is substantially perpendicular) the rotation axis of the movable gear 121. Furthermore, the movable gear 121 includes a gear portion 121i at its outer periphery.

[0105] Fixed gear 122 along Figure 11The fixed gear 122 rotates in the direction of arrow R2 in parts (c) and (d). The fixed gear 122 has a cam shape along the rotational direction (circumferential direction) on its surface located on the side of the movable gear 121 relative to the rotational axis. The fixed gear 122 includes a first fixed inclined surface portion 122a, a first fixed flat surface portion 122b, a first fixed vertical wall portion 122c, a second fixed vertical wall portion 122d, a second fixed inclined surface portion 122e, and a second fixed flat surface portion 122f. In the first fixed inclined surface portion 122a and the second fixed inclined surface portion 122e, the first fixed inclined surface portion 122a is disposed on the upstream side of the fixed gear 122 relative to the rotational direction, and the second fixed inclined surface portion 122e is disposed on the downstream side of the fixed gear 122 relative to the rotational direction. The first fixed inclined surface portion 122a is inclined relative to the rotational axis direction of the fixed gear 122 so as to separate from the movable gear 121 as it moves towards the upstream side of the fixed gear 122 relative to the rotational direction. Furthermore, the second fixed inclined surface portion 122e is inclined relative to the rotation axis direction of the fixed gear 122, so as to approach the movable gear 121 towards the upstream side of the fixed gear 122 with respect to the rotation direction. Furthermore, on the surface of the fixed base portion 122g, where the first fixed inclined surface portion 122a and the second fixed inclined surface portion 122e are formed, located on the side of the movable gear 121, a fixed protruding shape portion 122h including a first fixed vertical wall portion 122c and a second fixed vertical wall portion 122d is provided. Each of the first fixed vertical wall portion 122c and the second fixed vertical wall portion 122d extends along (in this embodiment, substantially parallel to) the rotation axis direction of the fixed gear 122. In the first fixed vertical wall portion 122c and the second fixed vertical wall portion 122d, the first fixed vertical wall portion 122c is disposed upstream of the fixed gear 122 with respect to the rotation direction, and the second fixed vertical wall portion 122d is disposed downstream of the fixed gear 122 with respect to the rotation direction. Each of the first fixed flat surface portion 122b and the second fixed flat surface portion 122f extends along a surface of the fixed gear 122 that intersects (in this embodiment, is substantially perpendicular) the rotation axis of the fixed gear 122. In the first fixed flat surface portion 122b and the second fixed flat surface portion 122f, the first fixed flat surface portion 122b is disposed upstream of the fixed gear 122 with respect to the rotation direction, and the second fixed flat surface portion 122f is disposed downstream of the fixed gear 122 with respect to the rotation direction. The first fixed flat surface portion 122b and the second fixed flat surface portion 122f are respectively disposed upstream and downstream with respect to the rotation direction of the fixed gear 122, while the fixed protruding shape portion 122h is sandwiched between them. Furthermore, the fixed gear 122 includes a gear portion 122i at its outer periphery.

[0106] Incidentally, in this embodiment, the movable gear 121 also has a cam shape (part) identical to the cam shape described above on the side opposite to the rotation axis direction of the movable gear 121 (at a position offset by 180 degrees relative to the rotation direction). Similarly, the fixed gear 122 also has a cam shape (part) identical to the cam shape described above on the side opposite to the rotation axis direction of the fixed gear 122 (at a position offset by 180 degrees relative to the rotation direction).

[0107] Figure 12 Parts (a), (b), and (c) are in Figure 11 The dashed portions in parts (b) and (d) show sectional views of the cam shapes of the movable gear 121 and the fixed gear 122, and schematically illustrate the operation of the drive connection mechanism 120 during the rotational operation of the drive roller 46. Figure 12 Each of sections (a), (b), and (c) illustrates the state of the movable gear 121 and the fixed gear 122 when the amount of waste toner in the waste toner collection container 10 (the rotational load torque of the waste toner delivery screw 113) is different, as will be described later.

[0108] The movable gear 121 is pushed towards the fixed gear 122 by the spring 124 with a spring force (spring pressure) Fs along the rotation axis of the movable gear 121. When the movable gear 121 rotates in the direction of arrow R1 by receiving a drive input, the first inclined surface portion 121a and the first fixed inclined surface portion 122a come into contact with each other, so that the movable gear 121 receives a reaction force Ft depending on the rotational load torque of the fixed gear 122. Figure 12 Part (a) shows a state where the amount of waste toner in the waste toner collection container 10 is less than a predetermined amount (here, this state is also referred to as the "normal state"). In this state, the amount of waste toner in the waste toner collection container 10 is less than a predetermined amount, and therefore, the rotational load torque of the fixed gear 122, which receives the conveying resistance of the waste toner, is less than a predetermined value. That is, the reaction force Ft applied to the movable gear 121 is less than the spring force Fs, and therefore, the first inclined surface portion 121a and the first fixed inclined surface portion 122a come into contact (engage) with each other, so that the driving force is transmitted from the movable gear 121 to the fixed gear 122. Further, the fixed gear 122 rotates in the direction of arrow R2.

[0109] When the amount of waste toner in the waste toner collection container 10 reaches a predetermined amount (nearly full in this embodiment), the rotational load torque of the fixed gear 122 increases, causing the reaction force Ft applied to the movable gear 121 to balance the spring force Fs. Then, as the amount of waste toner in the waste toner collection container 10 increases, such as Figure 12As shown in part (b), the first inclined surface portion 121a and the first fixed inclined surface portion 122a slide relative to each other. As a result, the movable gear 121 moves in a direction opposite to the pushing direction of the push spring 124 (the direction in which the movable gear 121 is separated from the fixed gear 122 along the rotation axis direction of the movable gear 121).

[0110] After that, as Figure 12 As shown in part (c), the first inclined surface portion 121a and the first fixed inclined surface portion 122a are in a separated state. Further, as... Figure 12 As shown in part (c), the flat surface portion 121b and the first fixed flat surface portion 122b are in contact (engaged) with each other, and the first vertical wall portion 121c and the first fixed vertical wall portion 122c are in contact (engaged) with each other. Therefore, when the amount of waste toner in the waste toner collection container 10 reaches a predetermined amount or more, the first vertical wall portion 121c and the first fixed vertical wall portion 122c are in contact with each other, so that the driving force is transmitted from the movable gear 121 to the fixed gear 122. That is, as long as the movable gear 121 rotates in the direction of arrow R1, the movable gear 121 will not return to the fixed gear 122. Figure 12 The state of part (a).

[0111] Incidentally, in this embodiment, both the first inclined surface portion 121a and the first fixed inclined surface portion 122a are made into surfaces inclined relative to the rotation axis direction of the movable gear 121. However, it may be necessary to make only at least one of these portions into such inclined surfaces. For example, one portion may be made into a surface inclined relative to the rotation axis direction of the movable gear 121, while the other portion may be made into a rib shape (part) or a boss shape (part) that contacts the inclined surface. Further, in this embodiment, both the first vertical wall portion 121c and the first fixed vertical wall portion 122c that contact each other are made into surfaces that are substantially parallel to the rotation axis direction of the movable gear 121. However, it may be necessary to make only at least one of these portions into such surfaces. For example, one portion may be made into a surface that is substantially parallel to the rotation axis direction of the movable gear 121, while the other portion may be made into a rib shape or a boss shape that contacts the surface. Further, in this embodiment, the flat surface portion 121b provided on the movable gear 121 as a limiting portion contacts the first fixed flat surface portion 122b of the fixed gear 122, thereby limiting the phase change of the fixed gear 122. However, according to Figure 12 As can be understood from part (c), the limiting portion (the flat surface portion at the top of the fixed protruding shape portion 122h) provided on the fixed gear 122 contacts the movable gear 121, so that the limiting portion can limit the phase change of the fixed gear 122. That is, it is only necessary to provide the limiting portion on at least one of the movable gear 121 and the fixed gear 122.

[0112] <Near-Full State Detection Method>

[0113] Will use Figure 13 Parts (a) and (b) and Figure 14 Parts (a) and (b) describe the detection mechanism 100 as a detection device (detection unit), which is capable of detecting the movement of the movable gear 121 in the direction of the rotation axis. Figure 13 Parts (a) and (b) are perspective views showing the detection mechanism 100 in this embodiment. Furthermore, Figure 14 Parts (a) and (b) show cross-sectional views of the detection mechanism 100 in this embodiment. The detection mechanism 100 is capable of detecting the movement of the movable gear 121 in the direction of the rotation axis, thereby enabling the detection mechanism 100 to detect when the rotational load torque of the waste toner delivery screw 113 reaches a predetermined value or above (overload state).

[0114] like Figure 13 Parts (a) and (b) and Figure 14 As shown in portions (a) and (b), the detection mark 130 and the detection sensor 131 are mounted to and held by a sensor holder 132 provided on and on the side plate 1g of the main assembly, which is a side plate provided on the main assembly 1a of the device. The detection mark 130 includes a mark rotation axis 130a, a movable receiving portion 130b that can contact the rod portion 123a of the detection rod 123 provided to the drive connection mechanism 120, a detection area 131c that can enter the detection sensor 131, and a light-shielding portion 130c that retracts from the detection area. The detection mark 130 is mounted to the sensor holder 132 so that it can rotate about the mark rotation axis 130a because the mark rotation axis 130a is rotatably supported by the sensor holder 132. Furthermore, the posture of the detection mark 130 is maintained by a spring and a stop (not shown), causing the movable receiving part 130b to move toward the detection rod 123 and the light-shielding part 130c to be in a position retracted from the detection area 131c (at least the optical axis of the detection light) of the detection sensor 131. In other words, the posture of the detection mark 130 is maintained. Figure 14In part (a) of the state. In this embodiment, the detection sensor 131 constituting the detection device is composed of a light blocking / light transmission detection sensor (photoelectric sensor). The detection sensor 131 has a U-shaped cross-section and includes a light projection part 131a, a light receiving part 131b, and a detection area 131c formed between the light projection part 131a and the light receiving part 131b. The detection area 131c forms the optical path of the detection light from the light projection part 131a toward the light receiving part 131b, and allows the light blocking part 130c of the detection mark 130 to be positioned therein. In this embodiment, the detection mechanism 100 is constituted by including the detection mark 130 and the detection sensor 131. In this embodiment, the detection mechanism 100 can detect whether the position of the movable gear 121 relative to the rotation direction is a first position (a state where the rotational load torque is less than a predetermined value) or a second position (a state where the rotational load torque is greater than or equal to a predetermined value) by detecting the light blocking state and the light transmission state by the detection sensor 131.

[0115] Figure 13 Part (a) and Figure 14 Part (a) shows a state where the amount of waste toner in the waste toner collection container 10 is less than a predetermined amount. That is, Figure 13 Part (a) and Figure 14 Part (a) shows the normal state in which the movable gear 121 and the fixed gear 122 are engaged with each other via the first inclined surface portion 121a and the first fixed inclined surface portion 122a. Figure 13 Part (b) and Figure 14 Part (b) shows the waste toner collection container 10 in a state where the amount of waste toner has reached a predetermined level, i.e., it is nearly full. That is to say, Figure 13 Part (b) and Figure 14 Part (b) shows the state in which the movable gear 121 and the fixed gear 122 are in contact with each other through the flat surface portion 121b and the first fixed flat surface portion 122b and through the first vertical wall portion 121c and the first fixed vertical wall portion 122c.

[0116] In this embodiment, when the detection rod 123 contacts the detection mark 130 as the movable gear 121 moves along the rotation axis, the detection mark 130 rotates around the rotation axis 130a, thereby causing the detection sensor 131 to detect the obstruction or transmission of light. Further, in Figure 13 Part (a) and Figure 14 In the state shown in part (a) (where the amount of waste toner in the waste toner collection container 10 is less than a predetermined amount), the detection rod 123 separates from the moving receiving part 130b of the detection mark 130. Furthermore, the light-shielding part 130c of the detection mark 130 retracts from the detection area 131c of the detection sensor 131. Figure 13Part (b) and Figure 14 As shown in part (b), when the amount of waste toner in the waste toner collection container 10 reaches a predetermined amount, the movable gear 121 and the detection rod 123 move along the rotation axis of the movable gear 121 through the above-described operation. When the rod portion 123a of the detection rod 123 contacts the moving receiving portion 130b of the detection mark 130 as it moves, the detection mark 130 rotates around the mark rotation axis 130a. As a result, the light-shielding portion 130c of the detection mark 130 enters the detection area 131c of the detection sensor 131 and blocks the optical axis of the detection light of the detection sensor 131. Therefore, the detection sensor 131 detects the light-shielding state, thereby the detection mechanism 100 can detect that the inside of the waste toner collection container 10 is nearly full. That is, the state of the detection sensor 131 can be switched to a light-transmitting state as a first state and a light-shielding state as a second state. The detection mark 130 switches the state of the detection sensor 131 to either the light-shielding state or the light-transmitting state. The detection flag 130 sets the state of the detection sensor 131 to a light-blocking state by blocking the light path of the detection sensor 131, and sets the state of the detection sensor 131 to a light-transmitting state by opening the light path of the detection sensor 131. The detection sensor 131 outputs different detection signals according to the light-blocking state and the light-transmitting state, respectively. In this embodiment, the output signal (detection signal) of the detection sensor is cut off (OFF) in the light-transmitting state and turned on (ON) in the light-blocking state. This detection signal is input to the controller 3. As a result, the controller 3 can determine (detect) that the state inside the waste toner collection container 10 is close to full.

[0117] Figure 15 Parts (a) and (b) respectively show examples of detection modes of the detection signal output from the detection sensor 131 when the detection mechanism 100 detects a near-full state (near-full state detection). During the rotation of the drive roller 46, under normal conditions, the detection sensor 131 outputs an OFF signal. Figure 15 Part (a) illustrates the detection mode in this case. When the amount of waste toner in the waste toner collection container 10 approaches a predetermined amount, it is detected by... Figure 12 As shown in part (b), the sensor 131 outputs an ON signal. However, the state of the waste toner in the waste toner collection container 10 is not necessarily stable, and therefore, in some cases, when the conveying resistance of the waste toner conveying screw 113 decreases due to factors such as vibration, the state of the movable gear 121 may return to its previous state. Figure 12 The state of part (a). Figure 15 Part (b) shows the detection mode in this case.

[0118] Figure 16This is a flowchart of the near-full state detection in this embodiment. Controller 3 performs control to start drive motor 5, for example, upon the start of imaging operation (S101).

[0119] When the controller 3 detects the ON signal of the detection sensor 131 (S102: Yes), it starts counting the near-full state determination time T1, and during the near-full state determination time T1, the controller 3 determines whether the ON signal is continuously detected (S102, S103). That is, the controller 3 determines whether the near-full state determination time T1 has elapsed while the ON signal is detected. The near-full state determination time is preset to the duration of the ON signal, which allows the waste toner collection container 10 to be determined to be in a near-full state with sufficient accuracy. Further, if the ON signal is continuously detected during the near-full state determination time T1 (S103: Yes), the controller 3 detects the near-full state and executes a near-full state notification (S104). Then, the controller 3 executes control to stop the drive motor 5, for example, as the imaging operation ends (S105). On the other hand, if an OFF signal is detected before the near-full state determination time T1 has elapsed, or if no ON signal of the detection sensor 131 is detected (S102: No), the controller 3 proceeds to S105.

[0120] exist Figure 15 At times t1 and t2 shown in part (b), the sensor 131 outputs an ON signal, but outputs an OFF signal before the near-full state determination time T1 has elapsed. Therefore, the controller 3 can determine that the waste toner collection container 10 is not in a near-full state. Then, if the sensor 131 outputs an ON signal during the near-full state determination time T1 (from time t3 to time t4), the controller 3 can determine that the waste toner collection container 10 is in a near-full state. Therefore, by performing near-full state detection after the near-full state determination time T1 has elapsed, the possibility of issuing a replacement warning before the originally determined replacement life is ended due to detecting near-full state under unstable rotational load torque of the stationary gear 122 can be reduced.

[0121] <Testing Methods for New Product Replacement>

[0122] Next, a method for detecting the replacement of waste toner with a new product will be described, which is a method for detecting that the waste toner collection container 10 (in this embodiment, the transfer unit 40) has been replaced with a new product. Here, the detection that the waste toner collection container 10 (in this embodiment, the transfer unit 40) has been replaced with a new product (determining whether the waste toner collection container 10 has been replaced with a new product) is also referred to as "new product replacement detection".

[0123] In this embodiment, the waste toner collection container 10 is disposed in the transfer unit 40, and therefore, as Figure 5 The transfer unit 40 shown is removed from the main equipment assembly 1a so that the waste toner collection container 10 can be replaced with a new one.

[0124] Figure 17 Parts (a), (b), and (c) are related to Figure 12 Similar schematic diagrams to those in (a), (b), and (c) schematically illustrate the operation of the drive connection mechanism 120 during new product replacement detection. Figure 17 Part (a) shows the positional relationship between the movable gear 121 and the fixed gear 122. That is, in the new state of the transfer unit 40, the movable gear 121 and the fixed gear 122 are mounted to the transfer unit 40 such that the second vertical wall portion 121d and the second fixed vertical wall portion 122d are in contact with each other, and the flat surface portion 121b and the second fixed flat surface portion 122f are in contact with each other. This positional relationship between the movable gear 121 and the fixed gear 122 is maintained by the pushing force of the push spring 124. When the drive roller 46 begins its rotational operation, the flat surface portion 121b and the second fixed flat surface portion 122f slide relative to each other, causing the movable gear 121 to move in the direction of arrow R1. Figure 17 As shown in part (b), when the flat surface portion 121b and the second fixed flat surface portion 122f separate from each other, the second inclined surface portion 121e and the second fixed inclined surface portion 122e come into contact with each other, causing the movable gear 121 to move in the pushing direction of the push spring 124 (the direction in which the movable gear 121 approaches the fixed gear 122 along the rotation axis of the movable gear 121). Then, as... Figure 17 As shown in part (c), the first inclined surface portion 121a and the first fixed inclined surface portion 122a engage with each other, such that the state of the movable gear 121 and the fixed gear 122 is switched to the normal state in which the driving force is transmitted from the movable gear 121 to the fixed gear 122.

[0125] Will use Figure 18 and Figure 19 Sections (a) to (c) describe the new product replacement detection process in this embodiment.

[0126] Figure 18 This is a flowchart of the new product replacement detection in this embodiment. Figure 19Parts (a) and (c) are time diagrams, which respectively illustrate examples of the detection modes when performing the new product replacement detection in this embodiment. In this embodiment, the transfer unit 40 is replaced when the power supply to the printer 1 is off or when the door 20 is open. Therefore, in this embodiment, the new product replacement detection is performed when the power supply to the printer 1 is detected to be on or the door 20 is closed. In this embodiment, the controller 3 is able to detect the closing of the door 20 based on a detection signal indicating the open / closed state of the door 20, which is input from a switch (not shown) provided on the door 20 of the printer 1 as an open / closed detection device.

[0127] When controller 3 detects that the power to printer 1 is turned on or door 20 is closed (S201), controller 3 determines whether it has detected an ON signal from sensor 131 (S202). If controller 3 detects an ON signal from sensor 131 (S202: Yes), controller 3 executes control to start drive motor 5 (S203). Then, controller 3 determines whether it has detected an OFF signal (S204). When controller 3 detects an OFF signal (S204: Yes), it starts counting the new product determination time T2, and controller 3 determines whether it has continuously detected an OFF signal during the new product determination time T2 (S204, S205). That is, controller 3 determines whether the new product determination time T2 has elapsed while controller 3 has detected an OFF signal. The new product determination time T2 is preset to the duration of the OFF signal, which allows transfer unit 40 to determine the product as new with sufficient accuracy. Then, if the controller 3 continuously detects an OFF signal during the new product determination time T2 (S205: Yes), the controller 3 detects that the transfer unit 40 is a new product and executes a predetermined process (S206) in the case where the transfer unit 40 is replaced with a new product. This predetermined process may include, for example, resetting (deactivating) the near-full state or the full state, and resetting the life counter of the transfer unit 40 to an initial value (e.g., zero). Further, the controller 3 controls the drive motor 5 to stop (S207) and ends the new product replacement detection. On the other hand, if the controller 3 does not detect an OFF signal from the detection sensor 131 in S204 (S204: No), the controller 3 waits for a preset new product detection time to elapse (S204, S208), and proceeds the process to S207, then ends the new product replacement detection. The new product detection time is preset to a time (predetermined time period) during which it is possible to determine with sufficient accuracy whether the transfer unit 40 is a new product (this setting may also be similar to the setting used for the near-full state determination time T1 described above). This situation occurs when the waste toner collection container 10 is nearly full or full and the transfer unit 40 is not new. Furthermore, if the controller 3 does not detect the ON signal of the detection sensor 131 in S202 (S202: No), the controller proceeds to S207 and ends the new product replacement detection. This situation occurs when the waste toner in the waste toner collection container 10 is in a normal state where its amount is less than a predetermined amount and the transfer unit 40 is not new.

[0128] Figure 19Part (a) shows the detection mode immediately following the replacement of the transfer unit 40 with a new product. The detection sensor 131 outputs an ON signal when the printer 1 is powered on, and then outputs an OFF signal approximately simultaneously with the start time t5 of the drive roller 46. Subsequently, when the detection sensor 131 outputs an OFF signal before the new product determination time T2 (before time t6), the controller 3 can determine that the transfer unit 40 has been replaced with a new product. Furthermore, the controller 3 can perform a predetermined process to reset the waste toner collection container 10 to a near-full or full state.

[0129] Figure 19 Part (b) illustrates the detection mode in which the transfer unit 40 is mounted to the main assembly 1a with the waste toner collection container 10 in a near-full or full state and the printer 1 is powered on or the door 20 is closed. As described above, after detecting a near-full state, the drive connection mechanism 120 is in a state of... Figure 12 The state shown in part (c) and not returned to Figure 12 The state of part (a). Therefore, when the transfer unit 40 is installed into the main assembly 1a of the device after detecting that it is close to full, the detection sensor 131 always outputs an ON signal. In this case, the controller 3 can determine that the waste toner collection container 10 (transfer unit 40) has not been replaced with a new one.

[0130] Figure 19 Part (c) shows an example of a detection mode, for instance, in which the waste toner dosage in the waste toner collection container 10 is close to a predetermined amount, and the transfer unit 40 is installed in the main component 1a of the device.

[0131] When the detection sensor 131 starts the new product replacement detection, it outputs an ON signal and then an OFF signal (time t7). However, before the new product determination time T2 (time t8) has elapsed, it is in a state where the detection is close to full and outputs an ON signal again.

[0132] Incidentally, when the waste toner collection container 10 contains less than a predetermined amount of waste toner in the transfer unit 40 installed in the main component 1a of the equipment, the detection mode is as follows: Figure 15 As shown in part (a).

[0133] In other words, based on the detection mode obtained during the new product replacement detection, the controller 3 can determine (detect) whether the transfer unit 40 (waste toner collection container 10) installed on the main component 1a of the equipment is a new transfer unit 40 (new waste toner collection container 10). Specifically, in this embodiment, based on the detection mode obtained during the new product replacement detection, the controller 3 can determine (detect) whether the transfer unit 40 installed on the main component 1a is a transfer unit 40 in which the waste toner dosage in the waste toner collection container 10 is less than a predetermined amount (normal state), a transfer unit 40 that is a new product (in a state where no waste toner is contained in the waste toner collection container 10), or a transfer unit 40 in which the waste toner dosage in the waste toner collection container 10 is more than a predetermined amount (close to full or full state).

[0134] Therefore, the imaging device (printer 1) includes: a main assembly 1a, which includes an imaging unit (cassette) P for forming an image using toner, a drive source (drive motor) 5 for generating driving force, and a detection unit (detection mechanism) 100 capable of taking a first state and a second state and outputting a detection signal according to each of the first and second states; and a replacement unit (transfer unit) 40, which can be installed to and removed from the main assembly 1a, and includes: a rotatable member (waste toner delivery screw). 113; a first rotatable member (movable gear) 121 that rotates by a driving force input from a drive source; a second rotatable member (fixed gear) 122 that is coaxially arranged with the first rotatable member 121 and configured to rotate by a driving force transmitted to it from the first rotatable member 121, so as to transmit a driving force toward the rotatable member 113; and a pressing member (pressing spring) 124 for pressing the first rotatable member 121 against the second rotatable member 122 along the rotation axis of the first rotatable member 121. The first rotatable member 121 can be moved to a first position in conjunction with the magnitude of the rotational load torque of the rotatable member 113 and the position of the second rotatable member 122 relative to the first rotatable member 121 with respect to the rotation direction of the first rotatable member 121. Figure 12 Part (a) Figure 17 Part (c)) and second position ( Figure 12 Part (c), Figure 17In part (a), the first position and the second position are different relative to the second rotatable member 122 with respect to the rotation axis direction of the first rotatable member 121, and the detection unit 100 changes its state between the first state and the second state according to the movement of the first rotatable member 121 between the first position and the second position. Further, in this embodiment, when the replacement unit 40 is installed to the main assembly 1a of the device, during a predetermined time period (new product detection time) from the start of the drive of the drive source 5, the detection mode of the detection signal output by the detection unit 100 is different in the following cases: when the drive of the drive source 5 starts, the first rotatable member 121 is in the first position and the rotational load torque of the rotatable member 113 is less than a predetermined value (normal state); when the drive of the drive source 5 starts, the first rotatable member 121 is in the second position and the rotational load torque of the rotatable member 113 is less than a predetermined value (new product state); and when the drive of the drive source 5 starts, the first rotatable member 121 is in the second position and the rotational load torque of the rotatable member 113 is greater than or equal to a predetermined value (nearly full state or full state).

[0135] Furthermore, in this embodiment, the replacement unit 40 includes a waste toner collection container 10 for containing waste toner collected in the main component 1a of the device, and a waste toner conveying member (waste toner conveying screw) 113 for conveying the waste toner contained in the waste toner collection container 10, and the rotatable member is the waste toner conveying member 113. Furthermore, in this embodiment, when the amount of waste toner contained in the waste toner collection container 10 is less than the predetermined amount, the rotational load torque of the waste toner conveying member 113 is less than a predetermined value; and when the amount of waste toner contained in the waste toner collection container 10 is greater than or equal to the predetermined amount, the rotational load torque of the waste toner conveying member 113 is greater than or equal to the predetermined value. The imaging device 1 includes a controller 3, which can detect whether the amount of waste toner contained in the waste toner collection container 10 is greater than or equal to the predetermined amount based on the detection signal output by the detection unit 100.

[0136] Furthermore, in this embodiment, for a replacement unit that is new, the first rotatable member 121 is installed such that the first rotatable member 121 is in a second position before the rotatable member begins to rotate, and based on the detection mode, the controller 3 can detect whether the replacement unit 40 installed to the main assembly 1a is new. Furthermore, in this embodiment, when a detection mode is obtained where the first rotatable member 121 is in the second position when the drive source 5 starts to drive and the rotational load torque of the rotatable member 113 is less than the aforementioned predetermined value, the controller 3 detects that the replacement unit 40 installed to the main assembly 1a is new. Furthermore, in this embodiment, the replacement unit 40 includes: an annular belt (intermediate transfer belt) 41 onto which an image formed by the imaging unit P using toner is transferred; a cleaning unit 43 for removing toner from the belt 41; and a waste toner collection container 10 for containing the toner removed from the belt 41 by the cleaning unit 43.

[0137] Furthermore, in this embodiment, at least one of the first rotatable member 121 and the second rotatable member 122 includes a cam-shaped portion (a first inclined surface portion 121a, a flat surface portion 121b, a first vertical wall portion 121c, a first fixed inclined surface portion 122a, a first fixed flat surface portion 122b, and a first fixed vertical wall portion 122c), which enables the position of the first rotatable member 121 relative to the second rotatable member 122 about the rotation axis direction of the first rotatable member 121 to move from a first position to a second position. When the drive source 5 is driven while the replacement unit 40 is installed on the main assembly 1a of the device, the aforementioned cam-shaped portion (first inclined surface portion 121a, first fixed inclined surface portion 122a, etc.) is configured such that: when the rotational load torque of the rotatable member 113 is less than a predetermined value, the position of the first rotatable member 121 is maintained at a first position; and when the rotational load torque of the rotatable member 113 changes from a rotational load torque less than a predetermined value to a rotational load torque greater than a predetermined value, the position of the first rotatable member 121 is maintained at a second position by moving the position of the first rotatable member 121 from the first position to the second position.

[0138] As described above, according to this embodiment, even if the waste toner collection container 10 is simply installed or removed before it is detected to be nearly full, it is possible to correctly detect whether the waste toner collection container 10 has been replaced with a new one (a new waste toner collection container). Furthermore, it is not necessary to separately install the fullness detection device and the new replacement detection device for the waste toner collection container 10 into the printer, and therefore, the possibility of increased device size and cost due to an increase in the number of parts can be reduced. In other words, according to this embodiment, with a simple construction that helps to suppress increases in device size and cost, it is possible to detect the replacement stage of the replacement unit and whether the replacement unit has been replaced with a new one.

[0139] [Example 2]

[0140] Next, another embodiment of this disclosure (Embodiment 2) will be described. The basic structure and operation of the imaging device in this embodiment are the same as those of the imaging device in Embodiment 1. Therefore, for elements having the same or corresponding functions or structures as the elements of the imaging device in Embodiment 1, their detailed descriptions will be omitted by adding the same reference numerals or symbols as in Embodiment 1.

[0141] <Drive Transmission Mechanism>

[0142] Figure 20 Parts (a) and (b), and parts (c) and (d) are perspective views and front views, respectively, which specifically show the movable gear 221 and the fixed gear 222 in this embodiment. Figure 20 Part (a) is a perspective view showing the surface of the movable gear 221 located on the side of the fixed gear 222 in the direction of the rotation axis of the movable gear 221. Figure 20 Part (b) is a front view showing the surface of the movable gear 221. Figure 20 Part (c) is a perspective view showing the surface of the fixed gear 222 located on the side of the movable gear 221 in the direction of the rotation axis of the fixed gear 222. Figure 20 Part (d) is a front view showing the surface of the fixed gear 222. The movable gear 221 and the fixed gear 222 include cam shapes (cam-shaped portions) that can engage with each other.

[0143] The drive transmission mechanism 220 in this embodiment includes a movable gear 221 and a fixed gear 222, instead of the movable gear 121 and fixed gear 122 of the drive connection mechanism 120 in Embodiment 1. In other respects, the construction of the drive transmission mechanism 220 is substantially the same as that of the drive connection mechanism 120 in Embodiment 1.

[0144] exist Figure 20In portions (a) and (b), the movable gear 221 rotates in the direction of arrow R1. The movable gear 221 has a cam shape along the rotational direction (circumferential direction) on its surface located on the side of the fixed gear 222 relative to the rotational axis. In this embodiment, the movable gear 221 includes a first inclined surface portion 221a, a flat surface portion 221b, and a second inclined surface portion 221c. In the first inclined surface portion 221a and the second inclined surface portion 221c, the first inclined surface portion 221a is disposed downstream of the movable gear 221 relative to the rotational direction, and the second inclined surface portion 221c is disposed upstream of the movable gear 221 relative to the rotational direction. The first inclined surface portion 221a is inclined relative to the rotational axis direction of the movable gear 221 so as to approach the fixed gear 222 towards the upstream side of the movable gear 221 relative to the rotational direction. Furthermore, the second inclined surface portion 221c is inclined relative to the rotation axis direction of the movable gear 221, so as to separate from the fixed gear 222 as it moves upstream of the movable gear 221 relative to the rotation direction. Furthermore, a flat surface portion 221b is formed on the surface located on the side of the fixed gear 222, on which the protruding shape portion 221d of the first inclined surface portion 221a and the second inclined surface portion 221c are formed. The flat surface portion 221b extends between the first inclined surface portion 221a and the second inclined surface portion 221c along the surface of the movable gear 221 that intersects (in this embodiment, is substantially perpendicular) the rotation axis direction of the movable gear 221. Furthermore, the movable gear 221 includes a gear portion 221e at its outer periphery.

[0145] exist Figure 20In parts (c) and (d), the fixed gear 222 rotates in the direction of arrow R2. The fixed gear 222 has a cam shape along the rotational direction (circumferential direction) on its surface located on the side of the movable gear 221 relative to the rotational axis. In this embodiment, the fixed gear 222 includes a first fixed inclined surface portion 222a, a fixed flat surface portion 222b, and a second fixed inclined surface portion 222c. In the first fixed inclined surface portion 222a and the second fixed inclined surface portion 222c, the first fixed inclined surface portion 222a is disposed upstream of the fixed gear 222 relative to the rotational direction, and the second fixed inclined surface portion 222c is disposed downstream of the fixed gear 222 relative to the rotational direction. The first fixed inclined surface portion 222a is inclined relative to the rotational axis direction of the fixed gear 222 so as to separate from the movable gear 221 as it moves towards the upstream side of the fixed gear 222 relative to the rotational direction. Furthermore, the second fixed inclined surface portion 222c is inclined relative to the rotation axis direction of the fixed gear 222, so as to approach the movable gear 221 towards the upstream side of the fixed gear 222 with respect to the rotation direction. Furthermore, a fixed flat surface portion 222b is formed on the surface of the fixed protruding shape portion 222d on the movable gear 221 side, where the first fixed inclined surface portion 222a and the second fixed inclined surface portion 222c are formed. The fixed flat surface portion 222b extends between the first fixed inclined surface portion 222a and the second fixed inclined surface portion 222c along the surface of the fixed gear 222 that intersects (in this embodiment, is substantially perpendicular) the rotation axis direction of the fixed gear 222. Furthermore, the fixed gear 222 includes a gear portion 222e at its outer periphery.

[0146] In other words, the movable gear 221 in this embodiment has a shape from the movable gear 121 in Embodiment 1 by removing the first vertical wall portion 121c and the second vertical wall portion 121d (i.e., the protruding shape portion 121h). Furthermore, the fixed gear 222 in this embodiment has a shape from the fixed gear 122 in Embodiment 1 by removing the first fixed vertical wall portion 122c and the second fixed vertical wall portion 122d (i.e., the fixed protruding shape portion 122h).

[0147] Incidentally, in this embodiment, the movable gear 221 also has a cam shape (part) identical to the cam shape described above on the side opposite to the rotation axis direction of the movable gear 221 (at a position offset by 180 degrees relative to the rotation direction). Similarly, the fixed gear 222 also has a cam shape (part) identical to the cam shape described above on the side opposite to the rotation axis direction of the fixed gear 222 (at a position offset by 180 degrees relative to the rotation direction).

[0148] Figure 21 Parts (a), (b), and (c) are in Figure 20The dashed portions in parts (b) and (d) show sectional views of the cam shapes of the movable gear 221 and the fixed gear 222, and schematically illustrate the operation of the drive transmission mechanism 120 during the rotational operation of the drive roller 46.

[0149] Similar to Embodiment 1, under normal conditions, the first inclined surface portion 221a of the movable gear 221 and the first fixed inclined surface portion 222a of the fixed gear 222 are in contact with each other, so that the driving force is transmitted from the movable gear 221 to the fixed gear 222. When the amount of waste toner in the waste toner collection container 10 reaches a predetermined amount, as the rotational load torque of the fixed gear 222 increases, such as Figure 21 As shown in part (b), the first inclined surface portion 221a and the first fixed inclined surface portion 222a slide relative to each other, causing the movable gear 221 to move in a direction opposite to the pushing direction of the push spring 124 (the direction in which the movable gear 221 is separated from the fixed gear 222 along the rotation axis direction of the movable gear 221). Thereafter, as... Figure 21 As shown in part (c), the first inclined surface portion 221a and the first fixed inclined surface portion 222a are separated from each other. Furthermore, the flat surface portion 221b and the fixed flat surface portion 222b are in contact with each other. When the movable gear 221 moves from... Figure 21 When part (c) rotates further in the direction of arrow R1, the following movement occurs. That is, as... Figure 21 As shown in part (d), while the second inclined surface portion 221c and the second fixed inclined surface portion 222c slide relative to each other, the movable gear 221 moves along the pushing direction of the push spring 124 (the direction in which the movable gear 221 approaches the fixed gear 222 along the rotation axis of the movable gear 221). Then, the state of the movable gear 221 and the fixed gear 222 returns to normal. Figure 21 The state of part (a).

[0150] Therefore, in this embodiment, when the reaction force Ft of the movable gear according to the magnitude of the rotational load torque of the fixed gear 122 is less than the spring force Fs, such as Figure 21 As shown in part (a), the movable gear 221 and the fixed gear 222 rotate in one direction when they are engaged. On the other hand, when the reaction force Ft exceeds the spring force Fs, the movable gear 221 rotates while moving along the rotation axis, resisting the pushing force of the spring 124. Then, from... Figure 21 Starting from state (a), the state follows Figure 21 Part (b) Figure 21 Part (c) and Figure 21 The order of part (d) is changed, and it returns to Figure 21The state of part (a). This operation is repeated.

[0151] Figure 22 Parts (a) and (b) are cross-sectional views showing the detection mechanism 100 in this embodiment, which is capable of detecting the movement of the movable gear 121 in the direction of the rotation axis. Figure 22 As shown in parts (a) and (b), the movable gear 221 and the fixed gear 222 are mounted to the drive transmission mechanism 220. Further, similar to Embodiment 1, the detection rod 123 moves with the movement of the movable gear 221 in the direction of the rotation axis, and the detection mark 130 rotates about the rotation axis 130a, such that the detection sensor 131 is placed in a state of light blocking or light transmission.

[0152] <Near-full status detection>

[0153] Figure 23 Parts (a) and (b) respectively illustrate examples of detection modes of the detection signal output from the detection sensor 131 when the detection mechanism 100 in this embodiment detects a near-full state (near-full state detection). During the rotation of the drive roller 46, in the normal state, the detection sensor 131 outputs an OFF signal. Figure 23 Part (a) illustrates the detection mode in this case. When the amount of waste toner in the waste toner collection container 10 approaches a predetermined amount, it is detected by referring to... Figure 21 The operation described in parts (a) to (d) involves the detection sensor 131 alternately and repeatedly outputting ON and OFF signals. Figure 23 Part (b) shows the detection mode in this case. At this time, based on the rotational speed of the movable gear 221, the detection sensor 131 outputs ON and OFF signals more than a predetermined number of times within a predetermined time. This predetermined time is called the near-full state determination time T3, and the ON and OFF signals are called pulse signals. Regarding the number of pulse signals, a pair of ON and OFF signals is counted as one (time). The controller 3 detects more than a predetermined number of pulse signals during the near-full state determination time T3 (from time t11 to time t12), enabling the controller 3 to determine that the waste toner collection container 10 is near-full. On the other hand, in Figure 23 At times t9 and t10 shown in part (b), the detection sensor 131 outputs an ON signal, but no pulse signal is detected more than a predetermined number during the near-full state determination time T3. Therefore, the controller 3 is able to determine that the waste toner collection container 10 is not in a near-full state. The near-full state determination time T3 and the number of pulse signals are preset so that the controller 3 can determine with sufficient accuracy the time and number of times the waste toner collection container 10 is in a near-full state.

[0154] Figure 24 This is a flowchart of the near-full state detection in this embodiment. Controller 3 performs control to start drive motor 5, for example, upon the start of imaging operation (S301).

[0155] When the controller 3 detects the ON signal of the detection sensor 131 (S302: Yes), it starts counting the number of pulse signals (S303) and starts counting the near-full state determination time T3 (S304). After the near-full state determination time T3 has elapsed, the controller 3 determines whether the number of pulse signals has reached a predetermined number or more (S305). Further, if the number of pulse signals has reached a predetermined number or more (S305: Yes), the controller 3 detects a near-full state and executes a near-full state notification (S306). Then, the controller 3 executes control to stop the drive motor 5, for example, as the imaging operation ends (S307). On the other hand, if the ON signal of the detection sensor 131 is not detected in S302 (S302: No), and if the number of pulse signals is less than a predetermined number in S305 (S305: No), the controller 3 proceeds to S307.

[0156] Therefore, by performing near-full condition detection after a near-full condition determination time T3, the possibility of issuing a replacement warning before the end of the initially determined replacement life can be reduced due to the detection of near-full condition under unstable rotational load torque of stationary gear 222.

[0157] <New Product Replacement Testing>

[0158] Figure 25 Parts (a), (b), and (c) are related to Figure 21 Similar schematic diagrams to those in (a), (b), and (c) schematically illustrate the operation of the drive transmission mechanism 220 during new product replacement detection. Figure 25 Part (a) shows the positional relationship between the movable gear 221 and the fixed gear 222. That is, in the new state of the transfer unit 40, the movable gear 221 and the fixed gear 222 are mounted to the transfer unit 40 such that the flat surface portion 221b and the fixed flat surface portion 222b are in contact with each other. This positional relationship between the movable gear 221 and the fixed gear 222 is maintained by the pushing force of the push spring 124. When the drive roller 46 begins its rotational operation, the flat surface portion 221b and the fixed flat surface portion 222b slide relative to each other, causing the movable gear 221 to move in the direction of arrow R1. Figure 25As shown in part (b), when the flat surface portion 221b and the fixed flat surface portion 222b separate from each other, the second inclined surface portion 221c and the second fixed inclined surface portion 222c come into contact with each other, causing the movable gear 221 to move along the pushing direction of the push spring 124 (the direction in which the movable gear 221 approaches the fixed gear 222 along the rotation axis of the movable gear 221). Then, as... Figure 25 As shown in part (c), the first inclined surface portion 221a and the first fixed inclined surface portion 222a engage with each other, such that the state of the movable gear 221 and the fixed gear 222 changes to the normal state in which the driving force is transmitted from the movable gear 221 to the fixed gear 222.

[0159] Will use Figure 26 Parts (a) and (b) and Figure 27 This embodiment describes the process for detecting new product replacement.

[0160] Figure 26 Parts (a) and (b) are time diagrams, which respectively show examples of the detection modes when performing the new product replacement detection in this embodiment. Figure 27 This is a flowchart of the new product replacement detection in this embodiment.

[0161] In this embodiment, the transfer unit 40 is replaced when the power to the printer 1 is off or when the door 20 is open. Therefore, in this embodiment, a new product replacement detection is performed when it is detected that the power to the printer 1 is on or the door 20 is closed.

[0162] When controller 3 detects that the power to printer 1 is turned on or door 20 is closed (S401), controller 3 determines whether it has detected an ON signal from sensor 131 (S402). If controller 3 detects an ON signal from sensor 131 (S402: Yes), controller 3 executes control to start drive motor 5 (S403). Then, controller 3 determines whether it has detected an OFF signal (S404). When controller 3 detects an OFF signal (S404: Yes), it starts counting the new product determination time T4, and controller 3 determines whether it has continuously detected an OFF signal during the new product determination time T4 (S404, S405). That is, controller 3 determines whether the new product determination time T4 has elapsed while controller 3 has detected an OFF signal. The new product determination time T4 is preset to the duration of the OFF signal, which allows transfer unit 40 to determine the product as new with sufficient accuracy. Then, if the controller 3 continuously detects an OFF signal during the new product determination time T4 (S405: Yes), the controller 3 detects that the transfer unit 40 is new and executes a predetermined process (S406) in the case where the transfer unit 40 is replaced with a new product. This predetermined process may include, for example, resetting (deactivating) the near-full state or the full state, and resetting the life counter of the transfer unit 40 to an initial value (e.g., zero). Further, the controller 3 controls the drive motor 5 to stop (S407) and ends the new product replacement detection. On the other hand, if the OFF signal of the detection sensor 131 is not continuous during the new product determination time in S404 and S405, the controller 3 waits for a preset new product detection time (S404, S408) to pass, proceeds to S407, and then ends the new product replacement detection. The new product detection time is preset to a time within which it is possible to determine with sufficient accuracy whether the transfer unit 40 is new (this setting may also be similar to the setting used for the near-full state determination time T3 described above). This situation occurs when the waste toner collection container 10 is nearly full or full and the transfer unit 40 is not new. Furthermore, if the controller 3 does not detect the ON signal of the detection sensor 131 in S402 (S402: No), the controller proceeds to S407 and ends the new product replacement detection. This situation occurs when the waste toner in the waste toner collection container 10 is in a normal state where its amount is less than a predetermined amount and the transfer unit 40 is not new.

[0163] Figure 26Part (a) shows the detection mode immediately following the replacement of the transfer unit 40 with a new product. The detection sensor 131 outputs an ON signal when the printer 1 is powered on, and then outputs an OFF signal approximately simultaneously with the start time t13 of the drive roller 46. Subsequently, when the detection sensor 131 outputs an OFF signal before the new product determination time T4 (before time t14), the controller 3 can determine that the transfer unit 40 has been replaced with a new product. Furthermore, the controller 3 can perform a predetermined process to reset the waste toner collection container 10 to a near-full or full state.

[0164] Figure 26 Part (b) illustrates the detection mode in which the waste toner collection container 10 is nearly full or full, the transfer unit 40 is mounted to the main assembly 1a, and the printer 1 is powered on or the door 20 is closed. As described above, after detecting a near-full state, the drive transfer mechanism 220 repeatedly... Figure 21 Part (a) to Figure 21 The operation of part (d) is as follows. Therefore, when the transfer unit 40 is installed into the main component 1a of the device after detecting that it is close to full, the detection sensor 131 repeatedly outputs ON and OFF signals during the new product determination time T4 (from time t15 to time t16). In this case, the controller 3 can determine that the waste toner collection container 10 (transfer unit 40) has not been replaced with a new product.

[0165] Incidentally, when the waste toner collection container 10 contains less than a predetermined amount of waste toner in the transfer unit 40 installed in the main equipment component 1a, the detection mode is as follows: Figure 23 As shown in part (a).

[0166] In other words, similar to Embodiment 1, in the new product replacement detection, based on the detection mode, the controller 3 can determine (detect) whether the transfer unit 40 (waste toner collection container 10) installed on the main component 1a of the equipment is a new transfer unit 40 (new waste toner collection container 10). Specifically, in this embodiment, based on the detection mode obtained in the new product replacement detection, the controller 3 can determine (detect) whether the transfer unit 40 installed on the main component 1a of the equipment is a transfer unit 40 in which the amount of waste toner in the waste toner collection container 10 is less than a predetermined amount (normal state), a transfer unit 40 that is a new product (a transfer unit 40 in which no waste toner is contained in the waste toner collection container 10), or a transfer unit 40 in which the amount of waste toner in the waste toner collection container 10 is more than a predetermined amount (close to full or full state). Incidentally, in this embodiment, during the new product replacement detection, when the waste toner collection container 10 is nearly full or full, when the drive motor 5 starts driving, except that the movable gear 121 is in the second position ( Figure 21 In addition to the case of part (c), there may also be a situation where the movable gear 121 is in the first position ( Figure 21 In part (a) of the case. However, also when the movable gear 121 is in the first position at the start of the new product replacement detection as described above, the movable gear 121 repeatedly moves to the second position and the first position during the subsequent new product replacement detection, causing the detection signal to repeatedly show the ON and OFF signals. Therefore, in the same case, the controller 3 is able to detect that the transfer unit 40 installed on the main component 1a of the equipment is a transfer unit 40 in which the waste toner collection container 10 is nearly full or full.

[0167] Therefore, in this embodiment, at least one of the first rotatable member (movable gear) 221 and the second rotatable member (fixed gear) 222 includes a cam-shaped portion (first inclined surface portion 221a, flat surface portion 221b, second inclined surface portion 221c, first fixed inclined surface portion 222a, fixed flat surface portion 222b, and second fixed inclined surface portion 222c), which enables the position of the first rotatable member 221 relative to the second rotatable member 222 about the rotation axis direction of the first rotatable member 221 to change from a first position ( Figure 21 Part (a)) moves to the second position ( Figure 21Part (c)). When the drive source 5 is driven with the replacement unit 40 installed to the main assembly 1a of the device, the cam-shaped portion (first inclined surface portion 221a, first fixed inclined surface portion 222a, etc.) is configured to: maintain the position of the first rotatable member 121 in the first position when the rotational load torque of the rotatable member 113 is less than a predetermined value; and repeat the movement of the position of the first rotatable member 221 from the first position to the second position and from the second position to the first position when the rotational load torque of the rotatable member 113 changes from a rotational load torque less than a predetermined value to a rotational load torque greater than a predetermined value.

[0168] As described above, similar effects to those in Example 1 can be achieved through the construction of this embodiment.

[0169] [Other embodiments]

[0170] The present disclosure has been described above based on specific embodiments, but the present disclosure is not limited to the above embodiments.

[0171] In the above embodiments, the case where the replacement unit is a waste toner collection container was described as an example, but the replacement unit is not limited to this. For example, in some cases, it is also desirable to detect the overload status of processing devices such as the toner delivery screw of the supply device for supplying toner to the developing apparatus and the developing roller of the developing apparatus. Furthermore, in some cases, it is also desirable to detect whether these devices are new. This disclosure also applies to other such replacement units.

[0172] Furthermore, waste toner is not limited to waste toner remaining on the image carrier after the transfer step. For example, in imaging equipment, in some cases, an operation is performed to discharge toner (in the case of a two-component developer, a developer including both toner and carrier) from the developing unit to refresh the developer in the developing unit. Furthermore, in some cases, a toner image (spot) for adjustment is formed on the image carrier that has not been transferred to the recording material. Waste toner contained in a waste toner collection container includes any of the toners described above (which may include a carrier). Furthermore, toner removed from the image carrier is not limited to toner removed from the intermediate transfer belt, but may also include toner removed from the photosensitive drum.

[0173] Furthermore, in the above embodiments, the state in which the rotational load torque of the waste toner conveying screw reaches a predetermined value or above is described as the state in which the waste toner collection container is nearly full. However, for example, this state can also be the state in which the waste toner collection container is full.

[0174] Furthermore, in the above embodiments, the case of transmitting driving force from a drive source (drive roller) for rotating the drive belt to the waste toner delivery screw is described; however, the imaging device may include a separate drive source for rotating the waste toner delivery screw.

[0175] Furthermore, in the above embodiments, the use of a photoelectric sensor as a detection sensor was described as an example. However, as a detection sensor, a mechanical switch that is turned on / off by a flag can also be used, for example.

[0176] While this disclosure has been described with reference to exemplary embodiments, it should be understood that this disclosure is not limited to the disclosed exemplary embodiments. The scope of the following claims is accorded the broadest interpretation so as to cover all such modifications and equivalent structures and functions.

Claims

1. An image forming apparatus comprising: a main assembly including an image forming portion configured to form an image with toner, a drive source configured to generate a driving force, and a detection portion capable of assuming a first state and a second state and configured to output a detection signal according to each of the first state and the second state; and a replacement unit capable of being detachably attached to the main assembly and including: a rotatable member; a first rotatable member configured to be rotated by inputting a driving force thereto from the drive source; a second rotatable member coaxially provided with the first rotatable member and configured to be rotated by transmitting a driving force thereto from the first rotatable member to transmit a driving force toward the rotatable member; and a push member configured to push the first rotatable member against the second rotatable member in a direction of an axis of rotation of the first rotatable member, wherein the first rotatable member is linked to move to a first position and a second position with respect to a position of the second rotatable member with respect to a direction of rotation of the first rotatable member according to a magnitude of a rotational load torque of the rotatable member, the first position and the second position being different with respect to the position of the second rotatable member in the direction of the axis of rotation of the first rotatable member, wherein the detection portion changes a state between the first state and the second state according to movement of the first rotatable member between the first position and the second position, and wherein, in a state where the replacement unit is attached to the main assembly, a detection pattern of the detection signal output by the detection portion is different in a case where the first rotatable member is in the first position and the rotational load torque of the rotatable member is less than a predetermined value when driving of the drive source is started, a case where the first rotatable member is in the second position and the rotational load torque of the rotatable member is less than the predetermined value when driving of the drive source is started, and a case where the first rotatable member is in the second position and the rotational load torque of the rotatable member is the predetermined value or more when driving of the drive source is started, within a predetermined period of time from the start of driving of the drive source.

2. The imaging device of claim 1, wherein, the replacement unit includes a waste toner collection container for accommodating waste toner collected in the main assembly, and a waste toner conveying member for conveying the waste toner accommodated in the waste toner collection container, and wherein the rotatable member is the waste toner conveying member.

3. The image forming apparatus according to claim 2, further comprising a controller capable of detecting whether or not an amount of waste toner accommodated in the waste toner collection container is the predetermined amount or more based on the detection signal output by the detection portion, wherein In a case where the amount of waste toner accommodated in the waste toner collection container is less than the predetermined amount, the rotational load torque of the waste toner conveying member is less than the predetermined value, and in a case where the amount of waste toner accommodated in the waste toner collection container is the predetermined amount or more, the rotational load torque of the waste toner conveying member is the predetermined value or more.

4. The imaging device of claim 3, wherein, The first rotatable member is installed to the replacement unit that is new in such a manner that the first rotatable member is in the second position before the rotation of the rotatable member is started, and The controller is capable of detecting whether the replacement unit installed to the main assembly is new based on the detection mode.

5. The imaging device of claim 4, wherein, In a case where the detection mode in which the first rotatable member is in the second position at the start of driving of the driving source and the rotational load torque of the rotatable member is less than the predetermined value is acquired, the controller detects that the replacement unit installed to the main assembly is new.

6. The imaging device of claim 2, wherein, The replacement unit includes: an endless belt onto which an image formed by toner of the image forming section is transferred, a cleaning section for removing toner from the endless belt, and a waste toner collection container for accommodating toner removed from the endless belt by the cleaning section.

7. The imaging device of claim 1, wherein, At least one of the first rotatable member and the second rotatable member includes a cam shape portion capable of moving the position of the first rotatable member with respect to the second rotatable member from the first position to the second position in the direction of the rotation axis of the first rotatable member.

8. The imaging device of claim 7, wherein, When the driving source is driven in a state where the replacement unit is installed to the main assembly, the cam shape portion is configured to: in a case where the rotational load torque of the rotatable member is less than the predetermined value, maintain the position of the first rotatable member in the first position; and in a case where the rotational load torque of the rotatable member changes from a rotational load torque less than the predetermined value to a rotational load torque of the predetermined value or more, maintain the position of the first rotatable member in the second position by moving the position of the first rotatable member from the first position to the second position.

9. The imaging device of claim 7, wherein, When the driving source is driven in a state where the replacement unit is installed to the main assembly, the cam shape portion is configured to: in a case where the rotational load torque of the rotatable member is less than the predetermined value, maintain the position of the first rotatable member in the first position; and in a case where the rotational load torque of the rotatable member changes from a rotational load torque less than the predetermined value to a rotational load torque of the predetermined value or more, repeat the movement of the position of the first rotatable member from the first position to the second position and the movement of the position of the first rotatable member from the second position to the first position.

Images