JP2006058729A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that since a shutter for a toner discharge port is opened by a projection fixedly arranged on a toner receiving side in the case the discharge port on the toner discharging side and the receiving port on the toner receiving side are connected together at the time of loading an image forming cartridge in an image forming apparatus, the shutter for the toner discharge port already begins opening in a state the toner discharge port and the toner receiving port overlap each other to some extent, but, they don't completely come in press contact with each other yet, consequently, the toner leaks or scatters outside the toner receiving port from the toner discharge port. <P>SOLUTION: The shutter 44 for opening/closing the toner discharge port 43 formed in the cleaning part of the process cartridge 21 is arranged, and the rotation of a photoreceptor drum 31 is transmitted to the shutter via a one-way clutch 48 with a limiter and a spiral gear 47, then, the toner discharge port 43 is opened while the photoreceptor drum 31 rotates, and the toner discharge port 43 is closed while the rotation of the photoreceptor drum 31 is stopped. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus using an electrophotographic system, such as a printer, a FAX, a copying machine, or the like.

In an electrophotographic apparatus, in a removable image forming cartridge, a photosensitive drum, a cleaning unit that removes residual toner remaining on the photosensitive drum, a conveyance unit that conveys the removed residual toner in the cleaning unit, and a conveyed residual In the case of having a toner discharge portion that discharges toner from the image forming cartridge, the toner discharge portion of the image forming cartridge is used to store the remaining toner discharged from the image forming cartridge in a toner collecting portion installed outside the image forming cartridge. And a toner recovery unit must be connected.
Conventionally, as the structure of this connecting portion, for example, an opening of a residual toner box is installed below the opening of the residual toner discharge port, and is provided at the residual toner discharge port when the image forming cartridge is attached to the apparatus. The lever of the residual toner shutter is pushed up by the protrusion formed on the residual toner box, and the discharge portion is opened by angular displacement by a predetermined angle against the biasing spring connected to the lever, and the residual portion removed by the cleaner portion is opened. There is a structure in which the toner is transported to the discharge port by the residual toner transport and discharged, and is closed by the restoring force of the biasing spring when the image forming cartridge is removed from the apparatus (see, for example, Patent Document 1).

JP-A-6-242710 (page 4-6, FIG. 6, FIG. 8)

  However, in the conventional apparatus described above, when the image forming cartridge is mounted, when the toner discharge side discharge port and the toner reception side reception port are connected to each other, the toner discharge port is fixed by a protrusion provided on the toner reception side. Since the toner discharge port and the toner receiving port overlap each other to some extent, and the toner discharge port shutter has already started to open, the shutter has already started to open. For this reason, there has been a problem that the toner leaks or scatters from the toner discharge port other than the toner receiving port.

  An object of the present invention is to solve the above-mentioned problems, prevent toner leakage and scattering when the image forming cartridge is attached / detached, and the image forming cartridge and the image forming apparatus main body to which the image forming cartridge is mounted leak or scatter. Another object of the present invention is to provide an image forming apparatus that is not contaminated with the toner. In addition, an image forming apparatus is provided in which the container and the image forming apparatus main body are not contaminated with leaked or scattered toner even when the container receiving the residual toner is attached to or detached from the image forming apparatus. There is.

  In the image forming apparatus, the present invention provides a toner carrier that carries toner, a removing unit that removes unnecessary toner remaining on the toner carrier, a toner receiver that contains the removed residual toner, and the toner receiver. A residual toner discharge port provided in the unit, a cleaning unit having an opening / closing member that opens and closes the residual toner discharge port, a residual toner container that stores the residual toner discharged from the cleaning unit, and an image forming apparatus Opening / closing member driving means for driving the opening / closing member based on a predetermined operation is provided.

  According to the present invention, the cleaning unit that temporarily stores the removed residual toner and discharges the residual toner from the residual toner discharge port, and the residual toner container of the discharge destination, leak or scatter the discharged residual toner. The remaining toner discharge port can be opened and closed in a state where it is connected so as not to be damaged.

Embodiment 1 FIG.
FIG. 1A is a side view showing a main part configuration of a process cartridge in the image forming apparatus according to Embodiment 1 of the present invention, and FIG. 2A is a top view of the main part. Moreover, FIG.1 (b) and FIG.2 (b) are the elements on larger scale of the area enclosed with the dashed-two dotted line in Fig.1 (a) and FIG.2 (a), respectively. FIG. 3 is a main part configuration diagram showing the main part configuration of the image forming apparatus according to the first embodiment of the present invention.

  The process cartridge 21 shown in FIG. 1 and FIG. 2 shows one of the four process cartridges 21 to 24 that are detachably mounted on the main body of the image forming apparatus 1 shown in FIG. However, toners of black (K), yellow (Y), magenta (M), and cyan (C) are respectively stored.

  As shown in FIG. 3, the image forming apparatus 1 includes process cartridges 21 to 24 that can be attached to and detached from the image forming apparatus main body, a residual toner container 3, an exposure device 4, a transfer belt unit 5, a fixing device 6, A main body cover 9 is provided that opens and closes when the paper cassette 7, the paper feed unit 8, and the process cartridges 21 to 24 are removed from the main body of the image forming apparatus. As described above, the portion of the image forming apparatus 1 excluding the removable process cartridges 21 to 24 is referred to as an image forming apparatus main body.

  As shown in FIG. 3, the process cartridges 21 to 24 are arranged in order of black (K), yellow (Y), magenta (M), and cyan (C) in order from the upstream side of the conveyance path 10 for the printing paper 11 described later. The process cartridges 21 to 24 for storing toner are arranged in series in order. Since the process cartridges 21 to 24 have the same configuration as described above, here, the configuration of the process cartridge 21 that stores black (K) toner is representatively described with reference to FIGS. 1 and 2. explain.

  The process cartridge 21 is recorded on the photosensitive drum 31 by exposure performed based on the print data in the photosensitive drum 31, the charging device 32 for charging the photosensitive drum 31, and the exposure device 4 (FIG. 3). A developing unit 33 that develops a toner image with toner 34 (in this case, black (K)) on the latent image to be printed, and printing paper conveyed by the transfer belt unit 5 along the conveyance path 10 as shown in FIG. 11 is provided with a cleaning unit 35 that removes the residual toner 34 remaining on the photosensitive drum 31 after the image is transferred to the photosensitive drum 31.

  Note that the XYZ coordinates in FIG. 3 take the X axis in the transport direction when the printing paper 11 shown in FIG. 3 passes through the process cartridges 21 to 24 and the Y axis in the rotation axis direction of the photosensitive drum 31. The Z axis is taken in a direction perpendicular to these two axes. In addition, even when XYZ coordinates are shown in other drawings to be described later, the axial directions of these coordinates indicate a common direction.

  As shown in FIG. 1B, the cleaning unit 35 includes a cleaning blade 41 made of urethane rubber that removes residual toner remaining on the photosensitive drum 31 after the transfer process, and residual toner removed by the cleaning blade 41. A waste toner receiving portion 45 that accommodates the spiral 42 and a spiral 42 made of resin or metal wire, and a part of the cartridge frame 51, which is rotatably held around the Y axis so as to be conveyed to one end of the process cartridge 21. In order to discharge the residual toner conveyed by the spiral 42 to the outside of the process cartridge 21, a toner discharge port 43 formed below the end of the waste toner receiving portion 45 and an opening of the toner discharge port 43 should be opened and closed. A cylindrical shutter 44 is provided that is rotatably held around the Y axis. As shown in FIG. 2A, the cleaning blade 41 and the spiral 42 are formed so as to substantially cover the entire region in the axial direction of the photosensitive surface of the photosensitive drum 31.

  On the other hand, as a drive mechanism for opening and closing the shutter 44 of the cleaning unit 35, as shown in FIG. 2, the drum gear 46 located at the end of the photosensitive drum 31 is engaged with the drum gear 46 to receive a driving force, and the rotation shaft A spiral gear 47 that passes through the shutter 44 and is coupled to the spiral 42 and rotates. The driven side is coupled to the shutter 44, and the driving side is fixed to the shaft of the spiral gear 47 to transmit the rotation of the spiral gear 47 to the shutter 44. A one-way clutch 48 with a limiter and a biasing spring 49 that constantly biases the shutter 44 in one direction are provided.

  4 is an external perspective view of the shutter 44, FIG. 5 is a partial external perspective view of the cartridge frame 51 that rotatably holds the shutter 44, and FIGS. It is a fragmentary perspective view for demonstrating the opening / closing operation | movement of a shutter. Note that the XYZ axes in each of these drawings indicate the arrangement direction when the depicted portion of each drawing constitutes the image forming apparatus 1 shown in FIG.

  The configuration and operation of the opening / closing mechanism of the shutter 44 will be described below with reference to FIGS.

  The shutter 44 has a hole 44 b having substantially the same shape as the toner discharge portion 43 formed in the waste toner receiving portion 45 of the cartridge frame 51 on the cylindrical side surface 44 a, and is rotatably installed in the cartridge frame 51. On the other hand, in the cartridge frame 51, the shutter 44 is held at a position where the hole 44b and the toner discharge portion 43 can overlap with each other, and a holding hole 51c that rotatably holds the shutter 44 and a receiving range that restricts the rotation range of the shutter 44. Surfaces 51a and 51b are formed.

  6A and 7A show a state in which the shutter 44 is rotatably held by the cartridge frame 51. FIGS. 6B and 7B show the state of the shutter 44. FIG. It is the elements on larger scale of Drawing 6 (a) and Drawing 7 (a) for showing the relation between a rotation position and opening and closing of a shutter.

  As shown in FIG. 6, the toner discharge port 43 of the cartridge frame 51 and the hole 44b of the shutter 44 are aligned with each other at the rotational position where the side surface 44d of the projection 44c of the shutter 44 contacts the receiving surface 51a. Is opened. As shown in FIG. 7, the toner discharge port 43 of the cartridge frame 51 and the hole 44b of the shutter 44 are shifted from each other at the rotation position where the side surface 44e of the projection 44c of the shutter 44 contacts the receiving surface 51b. The toner discharge port 43 is closed by the cylindrical surface 44, and the toner discharge port 43 is closed. Further, the shutter 44 is always urged by a biasing spring 49 in the direction in which the toner discharge port 43 is closed, that is, in the arrow B direction. Further, as described above, the shutter 44 is coupled to the shaft of the spiral gear 47 via the one-way clutch 48 with a torque limiter.

  The operation of the one-way clutch 48 with a torque limiter adopted here works in the same way as a centrifugal clutch as a clutch function, and the rotational force is driven while the spiral gear 47 on the driving side rotates at a predetermined rotational speed or more. When the rotation is transmitted to the shutter 44 on the side and the rotation of the spiral gear 47 is less than or equal to the predetermined number of rotations or is stopped, the shutter 44 on the driven side becomes free. As the limiter function, when the spiral gear 47 rotates in the direction of arrow A, the rotation is transmitted to the shutter 44 on the driven side within a range where the rotational load does not exceed the limiter value. Therefore, for example, when the rotation of the shutter 44 on the driven side is prevented, the spiral gear 47 continues to rotate in the A direction in the idling state while the rotation of the shutter 44 is stopped.

  Therefore, when the spiral gear 47 rotates in the direction of arrow A from the state shown in FIG. 7 where the toner discharge port 43 is blocked by the cylindrical surface of the shutter 44, the biasing spring 49 set within the limiter value is applied. When the shutter 44 is rotated in the same direction against the force, and the projection 44c of the shutter 44 comes into contact with the receiving surface 51a of the cartridge frame 51 as shown in FIG. Thus, the spiral gear 47 continues to rotate in the direction of arrow A while maintaining this contact state.

  When the operation of the photosensitive drum 31 is stopped and the spiral gear 47 is stopped, the shutter 44 is in a free state as described above. Therefore, only the shutter 44 is rotated in the arrow B direction by the restoring force of the biasing spring 49, It moves to the position shown in FIG. 7 where the toner discharge port 43 is closed.

  In the above configuration, as an example, a series of operations from when the process cartridge 21 is mounted to the main body of the image forming apparatus 1 until the toner discharge port 43 opens at a predetermined timing and the remaining toner is discharged will be described below. To do.

  First, before printing, when the process cartridge 21 is mounted at a predetermined position of the main body of the image forming apparatus 1 (FIG. 3), the discharge port 43 of the process cartridge 21 accommodates the remaining toner as shown in FIG. The opening 12a of the toner receiving portion 12 of the body 3 and the periphery are connected in a sealed state. However, the discharge port 43 at this time is in the closed state shown in FIG. When the image forming apparatus 1 is turned on, a warm-up operation before the printing operation is started, and the process cartridges 21 to 24, the transfer belt unit 5, and the fixing device 6 are operated.

  By this operation, the drum gear 46 installed at the end of the photosensitive drum 31 in the process cartridge 21 (FIG. 2) is driven by the main body of the image forming apparatus 1 and rotates in the arrow B direction (FIG. 1). . Along with this rotation, the spiral gear 47 that meshes with the drum gear 46 rotates in the direction of arrow A (FIG. 7A), and the shutter 44 starts to rotate in the direction of arrow A via the one-way clutch 48 with a torque limiter. At this time, the shutter 44 starts to rotate in the direction of arrow A against the biasing spring 49 from the state shown in FIG. 7, and the projection 44c abuts against the receiving surface 51a of the cartridge frame 51 in FIG. The rotation is stopped when the state shown is reached. At this time, by the action of the torque limiter of the one-way clutch 48, the spiral gear 47 continues to rotate in the same direction while keeping the shutter 44 in this rotation position, that is, the opening rotation position where the discharge port 43 is opened. Is possible. For this reason, the torque limiter is set so that the limiter value is equal to or higher than the rotational load of the shutter 44 including the biasing spring 49.

  With the above operation, while the shutter 44 maintains the opening rotation position described above, the discharge port 43 of the process cartridge 21 and the hole 44b of the shutter 44 are overlapped, and the discharge port 43 is in the open state. During this time, the rotation of the spiral 42 (FIG. 2) coupled to the spiral gear 47 causes the residual toner accumulated in the waste toner receiving portion 45 of the cleaning portion 35 to be conveyed to the end portion where the discharge port 43 is located, and the toner discharge port 43. Are discharged sequentially. At the time of warming up, no residual toner is generated on the photosensitive drum 31, so the residual toner accumulated in the waste toner receiving portion 45 is discharged.

  Thereafter, when the warm-up operation is completed and the rotation of the photosensitive drum 31 is stopped, the spiral gear 47 is stopped. Therefore, as described above, the driven shutter 44 is freed by the clutch function of the one-way clutch 48, so that only the shutter 44 rotates in the direction of arrow B by the restoring force of the biasing spring 49, and the side surface of the projection 44c. 44e moves until it comes into contact with the receiving surface 51b of the cartridge frame 51 and is in the state shown in FIG. At this time, the positions of the discharge port 43 and the hole 44b of the shutter 44 are shifted, and the discharge port 43 is closed.

  When this warming-up operation is completed, a printing operation is started after a correction operation such as a positional deviation correction is subsequently executed. During this misalignment correcting operation and printing operation, an electrostatic latent image is recorded on the photosensitive drum 31 by the exposure device 4, toner is developed on the electrostatic latent image by the developing unit 33, and further on the transfer belt unit 5. Alternatively, the toner image is transferred onto the printing paper 11. During this time, since the photosensitive drum 31 (FIG. 1) is driven to rotate in the direction of arrow B, the spurious gear 47 (FIG. 7) rotates in the direction of arrow A, and the discharge port 43 is opened to maintain this state. At the same time, the spiral 42 driven by the spiral gear 47 rotates in the same direction.

  On the other hand, as shown in FIG. 1, the residual toner remaining on the photosensitive drum 31 after the transfer is removed from the cleaning blade 41 of the cleaning unit 35 and collected in the waste toner receiving unit 45. Residual toner collected in the waste toner receiving portion 45 is conveyed toward the toner discharge port 43 by the rotating spiral 42, and from the toner discharge port 43 in the open state through the opening 12a of the toner receiving portion 12. Then, it is discharged to the residual toner container 3. Other process cartridges 22 to 24 mounted on the main body of the image forming apparatus 1 shown in FIG. 3 also discharge residual toner to the residual toner container 3 by the same configuration and operation as the process cartridge 21 described here. Is to be done.

  Note that the image forming apparatus 1 operates to move a process cartridge that is not used to a predetermined amount in order to bring the process cartridge that is not in use into a non-contact state with respect to the transfer belt unit 5 during the monochrome printing operation. For this reason, even if it is not possible to maintain a hermetic seal around the portion where the toner discharge port 43 (FIG. 1B) of each process cartridge and the opening 12a of the toner receiving portion 12 of the residual toner container 3 are connected, they have moved. Since the rotation of the photosensitive drum 31 of the process cartridge is stopped, the toner discharge port 43 is closed by the shutter 44, and scattering and leakage of residual toner can be minimized.

  Further, during transportation with the process cartridges 21 to 24 mounted on the main body of the image forming apparatus 1, a portion where the toner discharge port 43 and the opening 12 a of the toner receiving portion 12 of the remaining toner container 3 are connected by vibration due to transportation. Even if the surrounding seal cannot be maintained, the toner discharge port 43 is closed by the shutter 44, so that the scattering and leakage of toner can be minimized.

  As described above, according to the image forming apparatus of the first embodiment, the toner discharge port 43 in the process cartridges 21 to 24 and the opening 12a of the toner receiving portion 3 of the main body of the image forming apparatus 1 are hermetically sealed. Since the toner discharge port 43 is opened by the shutter 44 after being connected in the state, it is possible to prevent scattering and leakage of toner from the toner discharge port 43 when the process cartridge is mounted. Further, when the photosensitive drum 31 is stopped, the toner discharge port 43 is closed by the shutter 44, so that the process cartridges 21 to 24 and the residual toner container 3 are subjected to vibrations and sealed. Even if the state cannot be maintained, scattering and leakage of residual toner can be minimized.

Embodiment 2. FIG.
FIG. 8A is a side view showing a main part configuration of the process cartridge in the image forming apparatus according to the second embodiment of the present invention, and FIG. 9A is a top view of the main part. Moreover, FIG.8 (b) and FIG.8 (b) are the elements on larger scale of the area enclosed with the dashed-two dotted line in Fig.8 (a) and FIG.8 (a), respectively.

  The image forming apparatus employing the process cartridge 61 is mainly different from the image forming apparatus 1 (FIG. 3) employing the process cartridge 21 of the first embodiment shown in FIG. 1 is a structure of a drive mechanism that opens and closes 44). Therefore, in the image forming apparatus employing the process cartridge 61, the same reference numerals are given to the parts common to the image forming apparatus 1 (FIG. 3) of the first embodiment described above, or the description is omitted with the drawing omitted. Differences from the image forming apparatus 1 (FIG. 3) will be mainly described.

  The process cartridges 61 are also mounted on a total of four image forming apparatus bodies together with process cartridges containing different color toners, like the toner cartridge 21 in the image forming apparatus 1 (FIG. 3) of the first embodiment. However, since all of them have the same configuration, only the configuration of the process cartridge 61 for storing, for example, black (K) toner will be described below.

  FIG. 10 is an external perspective view of the shutter 64, and FIG. 11 is a partial external perspective view of the cartridge frame 62 that rotatably holds the shutter 64. As shown in FIG. 12 and 13 are partial perspective views for explaining the opening / closing operation of the shutter 64. FIG. Note that the XYZ axes of these drawings are assumed when the image forming apparatus of this embodiment in which the depiction portion of each figure is arranged in the same manner as the image forming apparatus 1 shown in FIG. 3 is configured. The arrangement direction of is shown.

  The configuration of the opening / closing mechanism of the shutter 64 and the operation of each part will be described below with reference to FIGS.

  The shutter 64 has a hole 64b having substantially the same shape as the toner discharge portion 43 formed in the waste toner receiving portion 45 (FIG. 11) of the cartridge frame 62 on the cylindrical side surface 64a (FIG. 10). It is installed in a rotatable manner. On the other hand, in the cartridge frame 62, the shutter 64 is held at a position where the hole 64b and the toner discharge portion 43 can overlap with each other, and a holding hole 62d that rotatably holds the shutter 64 and a receiving range that restricts the rotation range of the shutter 64. Surfaces 62a and 62b are formed. 12 and 13 show a state in which the shutter 64 is rotatably held by the cartridge frame 62. FIG.

  As shown in FIG. 12, the toner discharge port 43 of the cartridge frame 62 and the hole 64b of the shutter 64 are shifted from each other at the rotational position where the side surface 64d (FIG. 10) of the lever 64c of the shutter 64 contacts the receiving surface 62a. Thus, the toner discharge port 43 is closed by the cylindrical surface of the shutter 64, and the toner discharge port 43 is closed. As shown in FIG. 13, the toner discharge port 43 of the cartridge frame 62 and the hole 64 b of the shutter 64 are aligned with each other at the rotational position where the side surface 64 e (FIG. 10) of the lever 64 c of the shutter 64 contacts the receiving surface 62 b. The toner discharge port 43 is opened. Further, the shutter 64 has a direction in which the toner discharge port 43 is closed by the urging spring 63 stretched between the locking projection 62c of the cartridge frame 62 and the locking projection 64f (FIG. 10) of the shutter 64, that is, the Y axis. Always energized in the direction of the surrounding arrow A.

  The solenoid 71a is disposed in the main body of the image forming apparatus, and performs a suction operation of the plunger 71b in the Z-axis direction based on a control system command to be described later. Hereinafter, the solenoid 71a and the plunger 71b are collectively referred to as a plunger solenoid 71. The distal end portion of the plunger 71b engages with one end portion of a connecting lever 72 pivotally supported by the support portion 75 of the image forming apparatus main body, and the other end portion of the connecting lever 72 is connected to the image forming device. The device main body engages with one end portion of the action lever 73 held so as to be slidable in the Z-axis direction, and the other end portion of the action lever 73 is attached to the action lever 73 so that the lever 64c of the shutter 64 can be pressed. Abut. The connecting lever 72 is always urged in the direction of arrow A about the Y axis by an urging spring 74 stretched between the image forming apparatus main body.

  Accordingly, while the plunger solenoid 71 is not in operation, the shutter 64 has the lever 64c abutted against the receiving surface 62a of the cartridge frame 62 by the biasing force of the biasing spring 63 as shown in FIG. The closed rotation position is set to the closed state. On the other hand, when the plunger solenoid 71 is operated based on a control system command to be described later, as shown in FIG. 13, the plunger 71b is sucked and the connecting lever 72 is rotated in the direction of arrow B around the Y axis, thereby acting lever. 73 pushes up the lever 64 c to a position where it abuts against the receiving surface 62 b of the cartridge frame 62. As described above, the shutter 64 maintains the opening rotation position in which the toner discharge port 43 is opened while the plunger solenoid 71 is operating.

  FIG. 14 is a block diagram showing a main configuration of a portion related to the present invention in the control system of the image forming apparatus of the present embodiment. Hereinafter, the control system will be described with reference to FIG. 12, FIG. 13 and the common parts with reference to the image forming apparatus 1 of the first embodiment shown in FIG.

  In the figure, when the print control unit 101 receives an instruction to start printing from the host device, the print control unit 101 issues an instruction to the motor control unit 106 to drive the photoconductive drum 31 (FIG. 3), transfer, A belt driving motor 108 for driving the transfer belt of the belt unit 5 (FIG. 3), a paper feeding motor 109 for driving the paper feeding roller of the paper feeding unit 8 (FIG. 3), and a fixing roller of the fixing device 6 (FIG. 3). The fixing motor 110 to be driven is controlled to rotate at a predetermined operation timing and rotation speed, respectively. Also, the print control unit 101 issues an instruction to the high-voltage control unit 104 to charge the image forming unit charging device 32 (FIG. 1), the developing unit 33 (FIG. 1), and the transfer belt including the process cartridge 21 and the transfer belt unit 5. Control is performed so that a predetermined high voltage is applied to each high voltage application section of the unit 5, and the exposure control section 102 is instructed to write print data with the exposure head provided in the exposure apparatus 4 (FIG. 3). . Then, the solenoid control unit 111 is instructed to operate the solenoid 71a while the photosensitive drum drive motor 107 is rotating, for example.

  In the above configuration, as an example, a series of operations from when the process cartridge 61 is mounted to the main body of the image forming apparatus 1 until the toner discharge port 43 is opened at a predetermined timing and the remaining toner is discharged will be described below. To do.

  First, prior to printing, when the process cartridge 61 is mounted at a predetermined position of the main body of the image forming apparatus (see FIG. 3), the process as shown in FIG. The discharge port 43 of the cartridge 61 is configured to be connected to the opening 12a of the toner receiving portion 12 of the residual toner container 3 in a state where the periphery is sealed. Further, as shown in FIG. It moves to a position where it can come into contact with the tip of the action lever 73 held by the forming apparatus main body. The discharge port 43 at this time is closed by the shutter 64 when the process cartridge 61 is moved and immediately after mounting. The state of the plunger solenoid 71 and the shutter 64 shown in FIG. 12 corresponds to the state at the stage where the process cartridge 61 is mounted.

  When the image forming apparatus 1 is turned on, a warm-up operation before the printing operation is started, and the process cartridges 21 to 24, the transfer belt unit 5, and the fixing device 6 are operated.

  By this operation, the drum gear 46 installed at the end of the photosensitive drum 31 in the process cartridge 61 (FIG. 9) is driven from the main body of the image forming apparatus 1 and rotates in the direction of arrow B (FIG. 8). . Along with this rotation, the spiral gear 47 that meshes with the drum gear 46 starts to rotate in the direction of arrow A (FIG. 12). The print control unit 101 (FIG. 14) instructs the solenoid control unit 111 so that the solenoid 71a is in an operating state while the photosensitive drum 31 is rotating. As a result, as shown in FIG. 13, the plunger 71 b is sucked, and the shutter 64 overlaps the discharge port 43 of the process cartridge 61 and the hole 64 b of the shutter 64 as described above while the photosensitive drum 31 is rotating. Stops at the opening rotation position where the opening becomes the open state.

  With the above operation, while the shutter 44 remains in the opening rotation position, the residual toner accumulated in the waste toner receiving portion 45 is discharged by the rotation of the spiral 42 (FIG. 9) coupled to the spiral gear 47. Are transported to a certain end portion and sequentially discharged from the toner discharge port 43. At the time of warming up, no residual toner is generated on the photosensitive drum 31, so the residual toner accumulated in the waste toner receiving portion 45 is discharged.

  Thereafter, when the warm-up operation is finished and the rotation of the photosensitive drum 31 is stopped, the operation of the solenoid 71a is also stopped at the same time. For this reason, the connecting lever 72 pulls out the plunger 71b which is rotated in the direction of the arrow A from the state of FIG. 13 to the state of FIG. 12 by the urging force of the urging spring 74, and the shutter 64 is The biasing force of the biasing spring 63 rotates in the direction of arrow A from the opening rotation position shown in FIG. 13 to the closing rotation position shown in FIG. 12, and the discharge port 43 is closed.

  When this warming-up operation is completed, a printing operation is started after a correction operation such as a positional deviation correction is subsequently executed. During this misalignment correcting operation and printing operation, an electrostatic latent image is recorded on the photosensitive drum 31 by the exposure device 4, toner is developed on the electrostatic latent image by the developing unit 33, and further on the transfer belt unit 5. Alternatively, the toner image is transferred onto the printing paper 11. During this time, since the photosensitive drum 31 (FIG. 8) is driven to rotate in the direction of arrow B, the opening of the shutter 64 shown in FIG. 13 is again rotated by the solenoid 71a that is in an operating state while the photosensitive drum 31 is rotating. Rotate to the position to keep the outlet 43 open.

  On the other hand, as shown in FIG. 8, the residual toner remaining on the photosensitive drum 31 after the transfer is removed by the cleaning blade 41 of the cleaning unit 35 and collected in the waste toner receiving unit 45. The toner stored in the waste toner receiving portion 45 is conveyed toward the toner discharge port 43 by the rotating spiral 42, and from the toner discharge port 43 in the open state through the opening 12a of the toner receiving portion 12. The residual toner container 3 is discharged.

  In the present embodiment, an example in which the solenoid 71a is operated in accordance with the rotation operation of the photosensitive drum 31 is shown. However, the present invention is not limited to this. For example, after the photosensitive drum 31 is rotated. The solenoid 71a may be operated at the timing when the exposure by the exposure head 103 (FIG. 14) is started (that is, the timing when the actual printing operation is started). .

  As described above, according to the image forming apparatus of the second embodiment, it is possible to open and close the toner discharge port 43 at an arbitrary timing using the solenoid 71a. Therefore, the toner discharge port 43 is opened and closed at an optimal timing. As a result, it is possible to more reliably prevent the remaining toner from scattering and leaking from the toner discharge port 43 when the process cartridge is attached or after the attachment, as compared with the case of the first embodiment.

Embodiment 3 FIG.
FIG. 15 is a main part configuration diagram showing the main part configuration of the image forming apparatus according to the third embodiment of the present invention.

  The image forming apparatus 121 shown in FIG. 15 is mainly different from the image forming apparatus 1 (FIG. 3) of the first embodiment described above in that cleaning for removing residual toner attached to the transfer belt 125 of the transfer belt unit 5 is performed. This is a point where a part 122 is added. Therefore, in this image forming apparatus 121, parts common to the image forming apparatus 1 (FIG. 3) of the first embodiment described above are denoted by the same reference numerals, or the drawings are omitted and the description is omitted. Explain the point with emphasis.

  The cleaning unit 122 scrapes off the residual toner adhering to the transfer belt 125 and transports the residual toner removed by the cleaning blade 123 to one end of the transfer belt 125 in the width direction (Y-axis direction). The spiral 124 made of resin or metal wire is held so as to be rotatable about the Y axis, the residual toner receiving container 126 for storing the spiral 124, and the residual toner conveyed by the spiral 124 is discharged out of the residual toner receiving container 126. For this purpose, a toner discharge port 127 formed below the end is provided, and a cylindrical shutter 130 that is rotatably held around the Y axis is provided to open and close the opening of the toner discharge port 127. In addition, the remaining toner container 3 is formed with an opening 129a of a toner receiving portion 129 that is connected to the toner discharge portion 127 in close contact with the periphery.

  The driving mechanism for opening and closing the shutter 130 is assumed to be configured in the same manner as the opening and closing mechanism of the first embodiment described with reference to FIGS. 4 to 7, and description thereof is omitted here. However, the shutter 130 corresponds to the shutter 44 here. Further, in the first embodiment, the spiral gear 47 meshes with the drum gear 46 to obtain power. However, in this embodiment, the spiral gear 47 is integrated with a belt roller 128 that drives the transfer belt 125 instead of the drum gear 46. It is configured to obtain power by meshing with a gear (not shown) that rotates coaxially therewith. Further, in the first embodiment, the spiral gear 47 drives the spiral 42 or the shutter 44 directly or via the one-way clutch 48. In this embodiment, the spiral gear 47 or the shutter 130 is driven instead. To do.

  Due to the above configuration, the toner discharge port 127 is opened while the transfer belt 125 is moving, and is closed as the transfer belt 125 stops. Accordingly, during the printing operation, residual toner that has moved from the photosensitive drum 31 onto the transfer belt 125 and adhered thereto is removed by the cleaning unit 122 and is discharged into the residual toner container 3 from the toner discharge port 127.

  As another shutter opening / closing method, the method of the second embodiment described above can be adopted. In this case, the shutter 130 adopts the configuration of the shutter 64 shown in FIG. 10, and drives the plunger solenoid 71 to open and close it. The configuration thereof is assumed to be the same as that of the opening / closing mechanism of the second embodiment described with reference to FIGS. 10 to 13, and the description thereof is omitted here. However, in the second embodiment, the solenoid is controlled to operate when the photosensitive drum 31 (FIG. 1) rotates, but here the solenoid is controlled to operate when the belt drive motor 108 rotates.

  The above description has been given by taking as an example the case where the image forming apparatus 121 removes the residual toner remaining on the transfer belt 125 during the normal printing operation in which the toner image is transferred to the printing paper 11. The apparatus 121 is configured to cope with the adjustment of the developing bias described below.

  The toner density when printing on the printing paper 11 by the image forming apparatus 121 varies depending on environmental changes and changes with time. Therefore, the image forming apparatus 121 has an adjustment mode for adjusting the voltage applied to the developing roller of the developing unit 33 (FIG. 3) when the power is turned on or after printing a predetermined number of sheets. In this adjustment mode, a plurality of toner images having different toner density patterns (100% duty, 75% duty, 50% duty, etc.) are directly transferred onto the transfer belt 125. The toner images of these patterns transferred to the transfer belt 125 are printed on the density of each pattern by a density sensor (not shown) provided on the downstream side of the image forming unit including the process cartridges 21 to 24 and the transfer belt unit 5. Measure.

  The voltage applied to the developing roller is changed according to the pattern density measured at this time. The difference between the reference density and the detected pattern density is obtained in advance in an experiment in association with the development voltage and stored in the memory. When it is determined that the detected pattern density is lower than the reference, it is applied to the developing roller. The voltage is set higher in absolute value than the reference, and conversely, if it is determined that the detected pattern density is higher than the reference, the voltage applied to the developing roller is set lower in absolute value than the reference.

  The toner image directly formed on the transfer belt 125 in this way is measured for its density and then removed by the cleaning unit 122 in the same manner as the residual toner at the time of normal printing described above. The remaining toner container 3 is discharged.

  As described above, according to the image forming apparatus of the third embodiment, when the residual toner adhering to the transfer belt is discharged to the toner receiving portion of the residual toner container, the toner discharge port is open only when necessary. For example, even when the residual toner container is configured to be detachable, it is possible to prevent a situation in which toner leaks or scatters in the image forming apparatus.

  By combining the interlocking of the shutter with a component interlocking with the operation of the intermediate transfer unit in the intermediate transfer type image forming apparatus, it can be applied to the toner discharge port shutter of the cleaner unit in the intermediate transfer unit.

(A) is a side view which shows the principal part structure of the process cartridge in the image forming apparatus of Embodiment 1 of this invention, (b) is the elements on larger scale around the dashed-two dotted line in (a). is there. (A) is a principal part top view of Fig.1 (a), (b) is the elements on larger scale of the area enclosed with the dashed-two dotted line in (a). 1 is a main part configuration diagram showing a main part configuration of an image forming apparatus according to a first embodiment of the present invention; 3 is an external perspective view of a shutter according to Embodiment 1. FIG. FIG. 5 is a partial external perspective view of a cartridge frame that rotatably holds the shutter of FIG. 4. (A) is a fragmentary perspective view for demonstrating the opening / closing operation | movement of a shutter in the cleaning part in Embodiment 1, (b) is the elements on larger scale of (a). (A) is a fragmentary perspective view for demonstrating the opening / closing operation | movement of a shutter in the cleaning part in Embodiment 1, (b) is the elements on larger scale of (a). (A) is a side view which shows the principal part structure of the process cartridge in the image forming apparatus of Embodiment 2 of this invention, (b) is the elements on larger scale around the dashed-two dotted line in (a). is there. (A) is a principal part top view of Fig.1 (a), (b) is the elements on larger scale of the area enclosed with the dashed-two dotted line in (a). 6 is an external perspective view of a shutter according to Embodiment 2. FIG. FIG. 11 is a partial external perspective view of a cartridge frame that rotatably holds the shutter of FIG. 10. FIG. 10 is a partial perspective view for explaining the opening / closing operation of the shutter in the cleaning unit in the second embodiment. FIG. 10 is a partial perspective view for explaining the opening / closing operation of the shutter in the cleaning unit in the second embodiment. FIG. 4 is a block diagram illustrating a configuration of a main part of a control system of an image forming apparatus according to a second embodiment related to the present invention. It is a principal part block diagram which shows the principal part structure of the image forming apparatus of Embodiment 3 of this invention.

Explanation of symbols

1,121 image forming apparatus,
3 Remaining toner container,
4 exposure equipment,
5 Transfer belt unit,
6 fixing device,
7 Paper cassette
8 Paper feeder,
9 Body cover,
10 Transport route,
11 Printing paper,
12 Toner receiving part,
12a opening,
21-24, 61 process cartridge,
31 photoconductor drum,
32 charging device,
33 Development section,
34 Toner,
35,122 cleaning unit,
41,123 cleaning blade,
42,124 spiral,
43,127 Toner outlet,
44, 64, 130 shutter,
44a, 64a cylindrical side surface,
44b, 64b holes,
44c protrusion,
44d, 44e, 64d, 64e side surface,
45 Waste toner receiver,
46 Drum Gear,
47 Spiral gear,
47a rotating shaft,
48 one-way clutch,
49, 63 biasing spring,
51, 62 cartridge frame,
51a, 51b, 62a, 62b receiving surface,
51c, 62d holding holes,
62c, 64f locking projection,
64c lever,
71 Plunger solenoid,
71a solenoid,
71b plunger,
72 connecting lever,
73 working lever,
74 biasing spring,
75 support part,
101 print control unit,
102 exposure control unit,
103 exposure head,
104 high pressure control unit,
105 Image forming unit,
106 motor controller,
107 photosensitive drum drive motor,
108 belt drive motor,
109 paper feed motor,
110 fixing motor,
111 solenoid control unit,
125 transfer belt,
126 Residual toner receiving container,
128 belt rollers,
129 Toner receiving part.

Claims (7)

In the image forming apparatus,
A toner carrier for carrying toner;
Removal means for removing residual toner that is no longer necessary on the toner carrier, a toner receiving portion for storing the removed residual toner, a residual toner discharge port provided in the toner receiving portion, and opening and closing the residual toner discharge port Cleaning means having an opening / closing member for
A residual toner container for storing residual toner discharged from the cleaning means;
An image forming apparatus comprising: an opening / closing member driving unit that drives the opening / closing member based on a predetermined operation of the image forming apparatus.   2. The image forming apparatus according to claim 1, wherein the toner carrying member is a photosensitive member carrying a toner image.   The image forming apparatus according to claim 1, wherein the toner carrier is a belt having a function of conveying a recording medium.   The opening / closing member driving means sets the opening / closing member to a closed position for closing the residual toner discharge port when the toner carrier is not operating, and the opening / closing member when the toner carrier is operating. 4. The driving force transmitting means for operating the opening / closing member in conjunction with the operation of the toner carrier so as to be an opening position for opening the residual toner discharge port. The image forming apparatus described. The driving force transmission means is
A gear mechanism that rotates in conjunction with the operation of the toner carrier;
The image forming apparatus according to claim 4, further comprising: a one-way clutch with a torque limiter that transmits a rotational force of the gear mechanism to the opening / closing member. The opening / closing member driving means comprises:
A drive unit that acts on the opening and closing member to move to a closing position for closing the residual toner discharge port and an opening position for opening the discharge port;
The image forming apparatus according to claim 1, further comprising: a control unit that controls the drive unit.   The driving unit includes an urging unit that urges the opening / closing member to the closed position and a plunger solenoid that moves the opening / closing member to the opening position. During the operation of the toner carrier by the control unit, The image forming apparatus according to claim 6, wherein an opening / closing member is moved to the opening position.

Images