JP4731588B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus having a process unit in an electrophotographic image forming apparatus.

  Consumables used in electrophotographic image forming apparatuses eventually reach the end of their service life as they are used. For toner cartridges, there is no toner to be supplied in the container, for process units, when the developer has deteriorated in durability, for waste toner containers, when the container is full of waste toner, etc. Applicable.

  In general, an image forming apparatus has a configuration in which when a consumable item reaches the end of its life, it is detected and the user is prompted to replace it. One of the configurations is to provide a new / old detection mechanism for identifying whether a consumable is a new product or an old product. As a method of providing a new and old detection mechanism to detect the life of a consumable, it is conceivable to provide an electric memory on the consumable and write information on it. However, since the semiconductor memory is very expensive, there is a problem that the consumables are expensive and the running cost is increased.

In order to solve this problem, an image forming apparatus using an old and new detection mechanism having a relatively inexpensive configuration without using an expensive member such as a semiconductor memory in the old and new detection mechanism is disclosed (for example, see Patent Document 1). ).
JP 2003-316227 A

  By the way, in order to maintain high image quality, it is particularly important to replace the process unit among consumables in the image forming apparatus. Further, the image forming apparatus is required to be further downsized. As the image forming apparatus is downsized, the process unit also needs to be downsized. Therefore, it is also necessary to reduce the size of the new / old detection mechanism for identifying whether the process unit is new or old. However, Patent Document 1 has a problem in that a complicated configuration is used as the old and new detection mechanism, and thus it is not possible to sufficiently cope with the downsizing of the process unit.

  In view of the above problems, an object of the present invention is to provide an image forming apparatus that can identify whether a process unit is new or old regardless of downsizing of the image forming apparatus.

  The image forming apparatus of the present invention includes a process unit and a positioning unit.

The process unit includes a photoconductor and can be replaced in the image forming apparatus main body. The positioning unit is disposed on the front side of the image forming apparatus main body in order to position the process unit on the image forming apparatus main body .

The process unit in the image forming apparatus of the present invention is interlocked with the rotation of the photosensitive member when the positioning unit is closed after the process unit is mounted on the image forming apparatus body and then the exterior cover of the image forming apparatus body is closed. The image forming apparatus main body identifies whether the process unit is new or old depending on whether or not the image forming apparatus main body detects the operating section. It has new and old detection members that can be used. In the present invention, irreversibly rotating by a certain angle means that after rotating by a certain angle, it cannot rotate in the reverse direction and does not rotate more than a certain angle. The positioning unit in the image forming apparatus of the present invention has a detection mechanism capable of detecting that the process unit is new by being acted on by the action part when positioning the process unit on the image forming apparatus main body.
The process unit has old and new detection members on a surface corresponding to the side on which the positioning unit is provided when the process unit is mounted on the image forming apparatus main body. When the positioning unit is closed while the process unit is mounted on the image forming apparatus main body in a state where the process unit is new, the action portion in the old and new detection member acts on the detection mechanism. The process unit has a drive gear that receives a driving force for driving the components of the process unit at one end on the back side of the image forming apparatus main body, and is provided on the opposite side of the image forming apparatus main body. New and old detection members are provided on the front side.

In this configuration, by providing the positioning unit with the detection mechanism and further providing the process unit with the new and old detection members, the detection mechanism and the action part of the old and new detection members can be brought into contact with each other accurately. This is because the process unit is positioned on the apparatus main body by the positioning unit.
Also, with this configuration, when the positioning unit is opened with the process unit mounted on the image forming apparatus main body, the new and old detection members are exposed and visible, and it is easy to check whether the new and old detection members indicate the old or new state. it can.
Furthermore, with this configuration, it is possible to secure a space for installing the old and new detection members without increasing the size of the process unit.

  The positioning unit preferably has an opening / closing mechanism that can be opened and closed when the process unit is attached to and detached from the image forming apparatus main body.

  In this configuration, the process unit can be reliably positioned on the apparatus main body by opening and closing the positioning unit only when the process unit is attached to and detached from the apparatus main body.

  The process unit preferably has a receiving part for protecting the old and new detection members.

  In this configuration, the old and new detection members can be protected from damage and the like.

  The photoreceptor preferably has an interlocking gear that interlocks the old and new detection members with the rotating part of the photoreceptor.

  In this configuration, the rotation of the photoconductor can be used to interlock the old and new detection members. Thereby, an old and new detection member can be interlocked, without providing another drive source further.

  The old and new detection member has an engagement portion for preventing the action portion from rotating to a position where the detection mechanism acts after the interlocking of the old and new detection member, and the process unit is engaged with the engagement portion. It is preferable to have an engaging portion.

  In this configuration, the engaging part of the old and new detecting member engages with the engaged part of the process unit to suppress the rotation of the operating part of the old and new detecting member, so that the old and new detecting member that has been linked once comes into contact with the detecting mechanism. It can prevent rotating to a position.

  The image forming apparatus according to the present invention can identify whether the process unit is new or old regardless of downsizing of the image forming apparatus.

  Hereinafter, an image forming apparatus according to the best embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram illustrating a configuration of an image forming apparatus according to an embodiment of the present invention.

  The image forming apparatus 100 forms multicolor and single color images on a predetermined sheet (recording paper) in accordance with image data transmitted from the outside. The image forming unit 110, the automatic document processing apparatus 120, It is composed of The image forming apparatus 100 corresponds to the apparatus main body of the present invention. The image forming unit 110 includes an exposure unit 1, a developing unit 2, a photosensitive drum 3, a cleaner unit 4, a charger 5, an intermediate transfer belt 6, a fixing unit 7, a paper feed cassette 81, and a paper discharge tray 91. .

  A document placement table 92 made of transparent glass on which a document is placed is provided on the upper portion of the image forming unit 110. An automatic document processor 120 is attached to the upper side of the document table 92. An image reading unit 90 that reads an image of a document is provided below the document table 92. The automatic document processing device 120 automatically conveys the document on the document placing table 92. Further, the automatic document processing device 120 is configured to be rotatable in the direction of arrow M, and the document can be placed manually by opening the document table 92.

  Image data handled in the image forming apparatus 100 corresponds to a color image using each color of black (K), cyan (C), magenta (M), and yellow (Y). Accordingly, four development units 2, photosensitive drums 3, chargers 5 and cleaner units 4 are provided to form four types of latent images corresponding to the respective colors, and are respectively provided in black, cyan, magenta and yellow. These are set to form four image stations.

  The charger 5 is a charging means for uniformly charging the surface of the photosensitive drum 3 to a predetermined potential. In addition to the charger type as shown in FIG. 1, a contact type roller type or brush type charger is used. Sometimes used.

  The exposure unit 1 is configured as a laser scanning unit (LSU) provided with a laser emitting portion, a reflection mirror, and the like. The exposure unit 1 is provided with a polygon mirror that scans the laser beam and optical elements such as a lens and a mirror for guiding the laser beam reflected by the polygon mirror to the photosensitive drum. As the exposure unit 1, for example, a method using an EL or LED writing head in which light emitting elements are arranged in an array can be employed.

  The exposure unit 1 has a function of forming an electrostatic latent image corresponding to the image data on the surface thereof by exposing the charged photosensitive drum 3 according to the input image data. The developing unit 2 visualizes the electrostatic latent images formed on the respective photosensitive drums 3 with toner of four colors (YMCK). The cleaner unit 4 removes and collects toner remaining on the surface of the photosensitive drum 3 after development and image transfer.

  The intermediate transfer belt unit 6 disposed above the photosensitive drum 3 includes an intermediate transfer belt 61, an intermediate transfer belt driving roller 62, an intermediate transfer belt driven roller 63, an intermediate transfer roller 64, and an intermediate transfer belt cleaning unit 65. ing. Four intermediate transfer rollers 64 are provided for each color for YMCK.

  The intermediate transfer belt driving roller 62, the intermediate transfer belt driven roller 63, and the intermediate transfer roller 64 are driven to rotate by stretching the intermediate transfer belt 61. Further, the intermediate transfer roller 64 gives a transfer bias for transferring the toner image on the photosensitive drum 3 onto the intermediate transfer belt 61.

  The intermediate transfer belt 61 is provided in contact with each photosensitive drum 3. A function of forming a color toner image (multicolor toner image) on the intermediate transfer belt 61 by sequentially superimposing and transferring the toner images of the respective colors formed on the photosensitive drum 3 onto the intermediate transfer belt 61. have. The intermediate transfer belt 61 is formed in an endless shape using, for example, a film having a thickness of about 100 μm to 150 μm.

  Transfer of the toner image from the photosensitive drum 3 to the intermediate transfer belt 61 is performed by an intermediate transfer roller 64 that is in contact with the back side of the intermediate transfer belt 61. A high-voltage transfer bias (a high voltage having a polarity (+) opposite to the toner charging polarity (−)) is applied to the intermediate transfer roller 64 in order to transfer the toner image. The intermediate transfer roller 64 is based on a metal (for example, stainless steel) shaft having a diameter of 8 to 10 mm, and the surface thereof can be uniformly applied with a high voltage to the intermediate transfer belt 61 by a conductive elastic material. In this embodiment, a roller shape is used as the transfer electrode, but a brush or the like can also be used.

  As described above, the electrostatic images visualized according to the respective hues on the respective photosensitive drums 3 are laminated on the intermediate transfer belt 61. As described above, the laminated image information is transferred onto the sheet by the transfer roller 10 disposed at the contact position between the sheet and the intermediate transfer belt 61 by the rotation of the intermediate transfer belt 61.

  At this time, the intermediate transfer belt 61 and the transfer roller 10 are pressed against each other at a predetermined nip, and a voltage for transferring the toner onto the paper is applied to the transfer roller 10 (the polarity opposite to the toner charging polarity (−)). (+) High voltage). Further, in order to obtain the nip constantly, the transfer roller 10 uses either the transfer roller 10 or the intermediate transfer belt driving roller 62 as a hard material (metal or the like), and the other as a soft material such as an elastic roller (elastic rubber roller). Alternatively, a foaming resin roller or the like is used.

  Further, as described above, the toner adhering to the intermediate transfer belt 61 due to contact with the photosensitive drum 3 or the toner remaining on the intermediate transfer belt 61 without being transferred onto the sheet by the transfer roller 10 is used in the next step. In order to cause a color mixture of toner, the intermediate transfer belt cleaning unit 65 is configured to remove and collect the toner. The intermediate transfer belt cleaning unit 65 is provided with a cleaning blade as a cleaning member that contacts the intermediate transfer belt 61, for example, and the intermediate transfer belt 61 that contacts the cleaning blade is supported by an intermediate transfer belt driven roller 63 from the back side. ing.

  The paper feed cassette 81 is a tray for storing sheets used for image formation, and is provided below the exposure unit 1 of the image forming unit 110. A sheet used for image formation can also be placed in the manual sheet feeding cassette 82. Furthermore, a paper discharge tray 91 provided above the image forming unit 110 is a tray for collecting printed sheets face down.

  The image forming unit 110 is provided with a substantially vertical sheet conveyance path S for feeding the sheets of the sheet feeding cassette 81 and the manual sheet feeding cassette 82 to the sheet discharge tray 91 via the transfer roller 10 and the fixing unit 7. ing. In the vicinity of the paper transport path S from the paper feed cassette 81 or the manual paper feed cassette 82 to the paper discharge tray 91, pickup rollers 11a and 11b, a plurality of transport rollers 12a to 12d, a registration roller 13, a transfer roller 10, and a fixing unit. 7 etc. are arranged.

  The conveyance rollers 12 a to 12 d are small rollers for promoting and assisting conveyance of the sheet, and a plurality of conveyance rollers 12 a to 12 d are provided along the sheet conveyance path S. The pickup roller 11 a is provided near the end of the paper feed cassette 81, picks up sheets one by one from the paper feed cassette 81, and supplies them to the paper transport path S.

  The registration roller 13 temporarily holds the sheet being conveyed in the sheet conveyance path S. The sheet has a function of conveying the sheet to the transfer roller 10 at the timing when the leading edge of the toner image on the photosensitive drum 3 and the leading edge of the sheet are aligned.

  The fixing unit 7 includes a heat roller 71 and a pressure roller 72. The heat roller 71 and the pressure roller 72 are configured to rotate with the sheet interposed therebetween. The heat roller 71 is set to have a predetermined fixing temperature by the control unit based on a signal from the temperature detector, and is transferred to the sheet by thermally pressing the toner together with the pressure roller 72 to the sheet. The resulting multicolor toner image is melted, mixed, and pressed to thermally fix the sheet. Further, an external heating belt 73 for heating the heat roller 71 from the outside is provided.

  Next, the paper conveyance path will be described in detail. As described above, the image forming apparatus 100 is provided with the paper feed cassette 81 and the manual paper feed cassette 82 for storing sheets in advance. Pickup rollers 11a and 11b are arranged to feed sheets from the sheet feeding cassette 81 and the manual sheet feeding cassette 82, respectively, and guide the sheets one by one to the sheet conveyance path S.

  A sheet conveyed from the sheet feeding cassette 81 and the manual sheet feeding cassette 82 is conveyed to the registration roller 13 by the conveying roller 12a in the sheet conveying path S, and a timing at which the leading edge of the sheet and the leading edge of the image information on the intermediate transfer belt 61 are aligned. The image information is written on the sheet. Thereafter, the sheet passes through the fixing unit 7 so that unfixed toner on the sheet is melted and fixed by heat, and is discharged onto the sheet discharge tray 91 through the conveyance roller 12b.

  The above-mentioned conveyance path is for a single-sided printing request for a sheet. On the other hand, when a double-sided printing request is made, the trailing edge of the sheet that has finished single-sided printing and has passed through the fixing unit 7 as described above. When the sheet is held by the final conveying roller 12b, the conveying roller 12b reverses to guide the sheet to the conveying rollers 12c and 12d. Then, after printing is performed on the back surface of the sheet through the registration roller 13, the sheet is discharged to the discharge tray 91.

  FIG. 2 is a diagram in which the outer frame of the image forming apparatus according to the embodiment of the present invention is omitted.

  In the image forming apparatus 100, the toner usually remains on the photosensitive drum 3 after the transfer. Therefore, the image forming apparatus 100 includes a cleaner unit 4 for removing the toner remaining on the photosensitive drum 3 and a waste toner container 200 for storing the waste toner removed from the photosensitive drum 3 by the cleaner unit 4. It has been. The waste toner container 200 is detachable from the image forming apparatus 100.

  FIG. 3 is a diagram in which the outer frame and the waste toner container of the image forming apparatus according to the embodiment of the present invention are omitted.

  A toner discharge port 210 and a positioning unit 300 are provided on the back side of the waste toner container 200. The toner discharge port 210 is a passage for carrying the waste toner removed from the photosensitive drum 3 by the cleaner unit 4 to the waste toner container 200. The positioning unit 300 is a unit for positioning the process unit 400 including the photosensitive drum 3 and replaceable with respect to the image forming apparatus 100 with respect to the image forming apparatus 100.

  FIG. 4 is a diagram in which the outer frame, the waste toner container, and the positioning unit of the image forming apparatus according to the embodiment of the present invention are omitted.

  On the back side of the positioning unit 300, a developing unit 2 and a process unit 400 are provided. The developing unit 2 and the process unit 400 are detachable from the image forming apparatus 100.

  FIG. 5 is a diagram in which the outer frame, the waste toner container, the positioning unit, and the developing unit of the image forming apparatus according to the embodiment of the present invention are omitted.

  The image forming apparatus 100 includes an opening path 600. FIG. 5 shows a state in which the process unit 400 is attached to the opening path 600. The process unit 400 and the developing unit 2 are detachable along the opening path 600. The image forming apparatus 100 is mounted with the developing unit 2 after the process unit 400 is mounted.

  FIG. 6 is a diagram showing a positioning unit of the image forming apparatus according to the embodiment of the present invention.

  The positioning unit 300 includes a front member 330 and a back member 340. The positioning unit 300 includes operation members 311 and 312, rotation fulcrum members 321 and 322, and a detection switch 460. The operation members 311 and 312 and the rotation fulcrum members 321 and 322 correspond to the opening / closing mechanism of the present invention. The detection switch 460 corresponds to the detection mechanism of the present invention.

  The operation members 311 and 312 are knobs that are rotated by an operator in order to fix or release the positioning unit 300 from the image forming apparatus 100. The rotation fulcrum members 321 and 322 are fulcrums that are rotatably supported by the image forming apparatus 100. The positioning unit 300 can be opened and closed with the rotation fulcrum members 321 and 322 as fulcrums when the process unit 400 is attached to and detached from the image forming apparatus 100. The detection switch 460 can detect that the process unit 400 is new by being pressed by a pressing unit 410 provided in the process unit 400 described later when the positioning unit 300 positions the process unit 400. It is. The pressing part 410 corresponds to the action part of the present invention. That is, the detection switch 460 includes a portion that is pressed by the pressing portion 410, and when this portion is pressed, the electrical contact is turned on and it is identified that the process unit 400 is new. If this part is not pressed, the process unit 400 mounted at that time is identified as an old product.

  FIG. 7 is a view of the end surface of the photosensitive drum in the process unit of the image forming apparatus according to the embodiment of the present invention.

  7A and 7B are diagrams in which the drum cover 450 that covers the end surface of the photosensitive drum 3 is omitted. An interlocking gear 30 and a rotation stopper 32 are formed on the end surface (rotating portion) of the photosensitive drum 3. An initial detection gear 411 and a stopper shaft 446 are supported on the drum cover 450. The initial detection gear 411 corresponds to the new and old detection members of the present invention. A frame 415 is attached to the photosensitive drum 3. Further, the drum shaft 34 has a protruding shape.

  The initial detection gear 411 includes an interlocking gear 418 and is supported so as to be interlocked with the interlocking gear 30 about the shaft support portion 416. The initial detection gear 411 has a pressing part 410 and an engaging part 412. When the process unit 400 is mounted on the image forming apparatus 100, the pressing unit 410 is irreversibly rotated in the direction of the arrow P by a certain angle in conjunction with the rotation of the photosensitive drum 3. Rotating irreversibly by a certain angle means that the pressing portion 410 cannot rotate in the reverse direction after the pressing portion 410 has rotated by a certain angle due to the engaging action of the engaged portion 414 and the engaging portion 412 described later, and This means that it does not rotate beyond a certain angle. The frame 415 has an engaged portion 414. Once the engaging portion 412 is engaged with the engaged portion 414, after the completion of the interlocking of the initial detection gear 411, the engaging portion 412 rotates in the direction opposite to the arrow P until the position where the pressing portion 410 is detected again by the detection switch 460. Deter it. Further, when the engaging portion 412 comes to a position where it engages with the engaged portion 414, the interlocking gear 418 and the interlocking gear 30 are disengaged, so that the pressing portion 410 does not rotate any more. That is, the pressing unit 410 irreversibly rotates in the direction of arrow P by a certain angle. The initial detection gear 411 is used for identifying whether the process unit is new or old. The stopper shaft 446 supports the stopper arm 440 by applying an elastic force so that the stopper arm 440 presses the end surface of the photosensitive drum 3. The stopper arm 440 has a protrusion 442 and an arm 444. The rotation stopper 32 inhibits the rotation of the photosensitive drum 3 by engaging with the stopper arm 440. The drum shaft 34 protrudes in the axial direction of the photosensitive drum 3, is fitted into the positioning unit 300, and is positioned at an accurate position in the image forming apparatus 100.

  FIG. 7 shows a surface corresponding to the side on which the positioning unit 300 is provided when the process unit 400 is mounted on the image forming apparatus 100. The initial detection gear 411 contacts the detection switch 460 when the process unit 400 is mounted on the image forming apparatus 100 and the positioning unit 300 is closed. That is, when the positioning unit 300 is opened while the process unit 400 is mounted on the image forming apparatus 100, the initial detection gear 411 is exposed and can be visually checked, and it is easy to check whether the initial detection gear 411 indicates a new or old state. it can.

  FIG. 8 is a view showing a positioning unit of the image forming apparatus according to the embodiment of the present invention.

  The positioning unit 300 has a fitting portion 36. The positioning unit 300 is attached to the image forming apparatus 100 after the process unit 400 and the developing unit 2 are attached to the image forming apparatus 100. At this time, since the drum shaft 34 of the photosensitive drum 3 is fitted to the fitting portion 36 of the positioning unit 300, the process unit 400 is positioned at an accurate position. Since the developing unit 2 is fitted with the process unit 400, the developing unit 2 is also positioned at an accurate position.

  FIG. 9 is a diagram showing a developing unit of the image forming apparatus according to the embodiment of the present invention.

  The developing unit 2 has a side member 20. The side member 20 is fitted with the process unit 400. As described above, when the developing unit 2 is fitted to the process unit 400, the distance between the developing unit 2 and the process unit 400 is kept constant, and a high-quality image can be stably formed.

  FIG. 10 is a diagram showing a developing unit of the image forming apparatus according to the embodiment of the present invention.

  FIG. 10 is a view of the developing unit 2 as viewed from the opposite direction to FIG. The side member 20 has a stopper release protrusion 22. The stopper release protrusion 22 presses down the protrusion 442 when fitted with the process unit 400. Then, the arm 444 is separated from the end surface of the photosensitive drum 3, the engagement between the arm 444 and the rotation stopper 32 is released, and the photosensitive drum 3 can be rotated. This mechanism will be described with reference to FIGS.

  FIG. 11 is a diagram showing a process unit of the image forming apparatus according to the embodiment of the present invention.

  FIG. 11 is a diagram showing a new process unit 400. The process unit 400 has a drum cover 450 attached thereto. The drum cover 450 has a receiving part 420 and an opening 430. The receiving part 420 is a member that protects the pressing part 410 from damage or the like. The opening 430 is provided at a position where the protrusion 442 is exposed. By providing the opening 430 at this position, the stopper release protrusion 22 can press the protrusion 442 when the developing unit 2 and the process unit 400 are fitted.

  FIG. 11 shows a state before the initial detection gear 411 is interlocked with the rotation of the photosensitive drum 3. In this state, when the process unit 400 is mounted on the image forming apparatus 100 and positioned by the positioning unit 300, the pressing unit 410 presses the detection switch 460, so that the image forming apparatus 100 identifies that the process unit 400 is new. Can do.

  The process unit 400 has a drive gear that receives a driving force for driving the components of the process unit 400 at one end, and an initial detection gear 411 on the side opposite to the side where the drive gear is provided. With this configuration, an installation space for the initial detection gear 411 can be secured without increasing the size of the process unit 400.

  FIG. 12 is a diagram showing a process unit of the image forming apparatus according to the embodiment of the present invention.

  FIG. 12 is a diagram showing an old process unit 400. When the developing unit 2 is fitted to the process unit 400, the stopper release projection 22 presses the projection 442 exposed from the opening 430, and the arm 444 and the detent 32 are disengaged. Then, the photosensitive drum 3 can rotate, and the initial detection gear 411 is interlocked with the interlocking gear 30, so that the pressing unit 410 moves to the position of the receiving unit 420. When the pressing part 410 rotates to this position, the engaging part 412 engages with the engaged part 414, so that the pressing part 410 does not rotate to a position detected by the detection switch 460. Therefore, the image forming apparatus 100 does not identify that the process unit 400 is new.

  FIG. 13 is a diagram showing a process unit of the image forming apparatus according to the embodiment of the present invention.

  FIG. 13A is a diagram in which the drum cover 450 is omitted. FIG. 13A shows a new process unit 400. FIG. 13B is a diagram illustrating a state of engagement between the arm 444 and the rotation stopper 32. The central portion of the long stopper arm 440 is supported by a stopper shaft 446, and a spring is built in the stopper shaft 446. By this spring, the stopper arm 440 is urged so that the arm 444 side abuts on the photosensitive drum 3 so that the protruding portion 442 side is separated from the photosensitive drum 3. The photosensitive drum 3 is rotatable only in the direction of arrow N, and the rotation of the photosensitive drum 3 is suppressed by the arm 444 and the rotation stopper 32 engaging with each other.

  FIG. 14 is a diagram showing a process unit according to the embodiment of the present invention.

  FIG. 14A is a diagram in which the drum cover 450 is omitted. FIG. 14A shows an old process unit 400. FIG. 14B is a diagram illustrating a state where the engagement between the arm 444 and the rotation stopper 32 is released. The initial detection gear 411 has an interlocking gear 418. When the process unit 400 is new, the interlocking gear 418 meshes with the interlocking gear 30. When the stopper release protrusion 22 depresses the protrusion 442, the arm 444 is separated from the photosensitive drum 3, so that the engagement between the arm 444 and the rotation stopper 32 is released, and the photosensitive drum 3 can be rotated. Therefore, when the engagement between the arm 444 and the rotation stopper 32 is released, the initial detection gear 411 is interlocked with the direction of the arrow P as the photosensitive drum 3 rotates. When the photosensitive drum 3 rotates, the rotation stopper 32 also rotates. However, since the stopper shaft 446 is disposed away from the photosensitive drum 3 as shown in FIG. 14B, the rotation of the rotation stopper 32 is prevented. There is no blocking member. When the initial detection gear 411 is interlocked with a predetermined position or more, the engaging portion 412 engages with the engaged portion 414, so that it does not rotate in the direction opposite to the arrow P direction. As a result, the pressing unit 410 is fixed at the position shown in the figure and is recognized as an old product.

  FIG. 15 is a diagram in which the developing unit is fitted to the process unit of the image forming apparatus according to the embodiment of the present invention.

  When the side member 20 and the drum cover 450 are fitted, the positions of the process unit 400 and the developing unit 2 are determined in a single way. Therefore, since it does not wobble when attached to the image forming apparatus 100, a high-quality image can be formed. Further, when the process unit 400 and the developing unit 2 are mounted on the image forming apparatus 100, the developing unit 2 is mounted after the process unit 400 is mounted. By mounting in this order, the initial detection gear 411 is not erroneously interlocked during the mounting operation of the process unit 400.

  FIG. 16 is a block diagram of a main part of the image forming apparatus according to the embodiment of the present invention. This block diagram shows only the part relevant to the present invention.

  CPU 500 is connected to detection switch 460, counter 510, and display unit 520. The detection switch 460 generates an ON signal when pressed by the pressing unit 410. The counter 510 measures the size and number of sheets printed after the new process unit 400 is mounted. The display unit 520 displays various information of the image forming apparatus 100.

  When the detection switch 460 is pressed by the pressing unit 410, the information is transmitted to the CPU 500, and the CPU 500 transmits a signal so as to reset the count value of the counter 510. When the count value of the counter 510 reaches a predetermined value, the information is transmitted to the CPU 500, and the CPU 500 transmits a signal to the display unit 520 to display that the process unit 400 is to be replaced.

  FIG. 17 is a diagram in which the process unit of the image forming apparatus according to the embodiment of the present invention is attached to the image forming apparatus.

  FIG. 17 is a view immediately after the unused process unit 400 is attached to the image forming apparatus 100. FIG. 17 is a diagram showing the detection switch 460 with the front member 330 of the positioning unit 300 omitted. As already described, the positioning unit 300 includes the detection switch 460.

  A procedure for attaching the process unit 400 and the developing unit 2 to the image forming apparatus 100 will be described. First, the process unit 400 is attached to the image forming apparatus 100. Next, the developing unit 2 is attached to the image forming apparatus 100 so as to be fitted to the process unit 400. Finally, the process unit 400 and the developing unit 2 are positioned and fixed to the image forming apparatus 100 by the positioning unit 300.

  When the positioning unit 300 fixes the process unit 400 and the developing unit 2 to the image forming apparatus 100, the detection switch 460 is pressed by the pressing unit 410. The detection switch 460 generates an ON signal when pressed by the pressing unit 410, and causes the image forming apparatus 100 to identify that the process unit 400 is new.

  FIG. 18 is a diagram when the process unit according to the embodiment of the present invention is attached to the image forming apparatus and the use of the process unit is started.

  When the use of the process unit 400 is started, the initial detection gear 411 is interlocked with the rotation of the photosensitive drum 3, so that the pressing unit 410 moves to the position of the receiving unit 420. At this position, the initial detection gear 411 ends interlocking. In this position, since the pressing unit 410 does not press the detection switch 460, the counter 510 is not reset. Further, at this position, the engaging portion 412 and the engaged portion 414 are engaged and the initial detection gear 411 finishes interlocking. Therefore, even if the process unit 400 is once removed and remounted, the position of the pressing portion 410 remains the same. Will never return. For this reason, the pressing unit 410 does not press the detection switch 460 again. Therefore, the usage of the process unit 400 is accurately counted by the counter 510 no matter how many times the process unit 400 is attached in the middle.

  Finally, the description of the above-described embodiment is to be considered in all respects as illustrative and not restrictive. The scope of the present invention is shown not by the above embodiments but by the claims. Furthermore, the scope of the present invention is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

1 is a diagram illustrating a configuration of an image forming apparatus according to an embodiment of the present invention. 1 is a diagram illustrating an outer frame of an image forming apparatus according to an embodiment of the present invention. FIG. 3 is a diagram in which an outer frame and a waste toner container of the image forming apparatus according to the embodiment of the present invention are omitted. FIG. 4 is a diagram in which an outer frame, a waste toner container, and a positioning unit of the image forming apparatus according to the embodiment of the present invention are omitted. FIG. 3 is a diagram in which an outer frame, a waste toner container, a positioning unit, and a developing unit of the image forming apparatus according to the embodiment of the present invention are omitted. FIG. 3 is a diagram illustrating a positioning unit of the image forming apparatus according to the embodiment of the present invention. FIG. 3 is a diagram of an end surface of a photosensitive drum in a process unit of an image forming apparatus according to an embodiment of the present invention. FIG. 3 is a diagram illustrating a positioning unit of the image forming apparatus according to the embodiment of the present invention. FIG. 2 is a diagram illustrating a developing unit of the image forming apparatus according to the embodiment of the invention. FIG. 2 is a diagram illustrating a developing unit of the image forming apparatus according to the embodiment of the invention. 1 is a diagram illustrating a process unit of an image forming apparatus according to an embodiment of the present invention. 1 is a diagram illustrating a process unit of an image forming apparatus according to an embodiment of the present invention. 1 is a diagram illustrating a process unit of an image forming apparatus according to an embodiment of the present invention. It is a figure which shows the process unit which concerns on embodiment of this invention. FIG. 3 is a diagram in which a developing unit is fitted in a process unit of the image forming apparatus according to the embodiment of the present invention. 1 is a block diagram of a main part of an image forming apparatus according to an embodiment of the present invention. 2 is a view immediately after an unused process unit 400 is attached to the image forming apparatus 100. FIG. FIG. 3 is a diagram when the process unit according to the embodiment of the present invention is attached to the image forming apparatus and the use of the process unit is started.

Explanation of symbols

3-Photosensitive drum 30-Interlocking gear 100-Image forming apparatus 300-Positioning unit 311, 312-Operation member 321, 322-Rotating fulcrum member 400-Process unit 411-Initial detection gear 412-Engagement unit 414-Engagement Joint section 420-receiving section 460-detection switch

Claims (5)

A process unit having a photoconductor and replaceable in the image forming apparatus main body;
A positioning unit disposed on the front side of the image forming apparatus main body to position the process unit on the image forming apparatus main body;
With
The process unit is irreversible in conjunction with rotation of the photosensitive member when the positioning unit is closed after the process unit is mounted on the image forming apparatus body and then the exterior cover of the image forming apparatus body is closed. The image forming apparatus main body identifies whether the process unit is new or old based on whether the image forming apparatus main body detects the operating section. It has new and old detection members that can
The positioning unit has a detection mechanism capable of detecting that the process unit is new by being acted on by the action portion when positioning the process unit on the image forming apparatus main body,
The process unit has the old and new detection members on a surface corresponding to a side on which the positioning unit is provided when the process unit is mounted on the image forming apparatus main body.
When the positioning unit is closed in a state where the process unit is mounted on the image forming apparatus main body in a state where the process unit is new, the action portion in the old / old detection member acts on the detection mechanism ,
The process unit has a drive gear that receives a driving force for driving the components of the process unit at one end on the back side of the image forming apparatus main body, and is opposite to the side on which the drive gear is provided. The image forming apparatus having the new and old detection members on the front side of the image forming apparatus main body . The image forming apparatus according to claim 1, wherein the positioning unit includes an opening / closing mechanism that can be opened and closed when the process unit is attached to and detached from the image forming apparatus main body. The image forming apparatus according to claim 1, wherein the process unit includes a receiving unit that protects the old and new detection member. The image forming apparatus according to claim 1, wherein the photoconductor includes an interlocking gear that interlocks the old and new detection member with a rotating portion of the photoconductor. The old and new detection member has an engagement portion for preventing the action portion from rotating to a position where the detection mechanism is pressed after the interlocking of the old and new detection member is completed,
The image forming apparatus according to claim 1, wherein the process unit includes an engaged portion that engages with the engaging portion.

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