JP2005049850A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus which can easily prevent the occurrence of toner blocking even when a carrying pipe is bent in a toner carrying path and further which can prevent the occurrence of the problem of generation of abnormal sound such as friction sound in a bent part, weight increase of a carrying coil itself, wasteful loading onto the carrying pipe and power consumption increase when driving the image forming apparatus. <P>SOLUTION: In a pipe member 32 of a toner carrying path X, at a perpendicular part Y toner is carried till a horizontal part Z by free fall utilizing gravity and at the horizontal part Z toner is carried till a toner recovery tank 34 by the carrying coil 33. A projection 31 of a pipe member exciting means collides with the perpendicular part Y attendant upon rotation of a flywheel 30 equipped therewith. Thereby the perpendicular part Y is excited by addition of impact to prevent the toner from adhering onto an inner wall of the pipe member 32. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus represented by a copying machine or a printer. In particular, the present invention relates to an image forming apparatus provided with means for preventing toner blocking in a toner conveyance path.

  An image forming apparatus configured as a copying machine, a printer, a facsimile machine, or a complex machine thereof has a plurality of toner conveyance paths for collecting or supplying toner. An example of the toner conveyance path is a toner conveyance path for the purpose of toner recycling for collecting a reusable toner in a toner collection tank.

  In the image forming apparatus, residual toner adhering to the surface of the photosensitive drum is cleaned electrically or mechanically by a cleaning device. The toner that can be stored and reused in the cleaning device is then transported from the cleaning device to a toner recovery tank through a toner transport path. In the toner transport path, generally, a spiral transport coil is provided in a transport pipe for transporting toner, and the toner is transported using the transport action of a rotating screw.

In such a toner transport mechanism, toner adheres to the inner wall of the transport pipe, so that toner transport may be hindered, so-called toner blocking may occur. As a means for preventing this toner blocking, as shown in, for example, Patent Document 1, a protrusion member that protrudes inside the conveyance pipe is provided, and the collision occurs between the protrusion member and the conveyance coil when the conveyance coil rotates. It is known that the conveying pipe is vibrated by an impact to prevent toner from adhering to the inner wall of the conveying pipe. In the toner transport device described in Patent Document 1, toner is transported by the rotation of the transport coil, and a transport coil that reaches from the toner transport inlet of the transport pipe to the toner transport outlet is used.
Japanese Patent Laid-Open No. 2001-66894 (5th page, FIG. 1)

  In recent years, as the internal mechanism of the image forming apparatus has been saved and the size of the image forming apparatus itself has been reduced, the transport pipe is accommodated in the image forming apparatus with one or several bent portions. It is often done. Thus, as in the toner transport device described in Patent Document 1, when a transport coil extending from the toner transport inlet to the toner transport outlet of the transport pipe is used, the transport coil and the transport are near the bent portion of the transport pipe. There is a problem that abnormal noise such as frictional noise with the inner wall of the pipe is generated. In addition, when the transfer coil is passed through the entire length of the transfer pipe, the weight of the transfer coil itself is not negligible, and a load is applied to the transfer coil due to the friction between the transfer coil and the transfer pipe. This also increases the power consumption.

  Further, if the conveying pipe is bent as described above, the conveying coil is deformed and a portion that does not follow the inner diameter of the pipe is generated. Therefore, the toner stays in the portion that does not follow the conveying coil, and the toner stays in the toner. There is no denying the possibility of blocking.

  The present invention has been made in view of the above points, and an object of the present invention is to easily prevent occurrence of toner blocking even when the conveyance pipe is bent in the toner conveyance path. It is possible to prevent the occurrence of problems such as the generation of abnormal noise such as friction noise at the bent part of the conveyance pipe, the increase in the weight of the conveyance coil itself, the useless load on the conveyance pipe, and the increase in power consumption when driving the image forming apparatus. An image forming apparatus is provided.

  In order to solve the above-described problems, the present invention provides an image forming apparatus comprising: a main body driving unit that drives the main body of the image forming apparatus; and a pipe member that conveys toner and that partially or entirely extends in the vertical direction. A pipe member vibration means for vibrating the pipe member using the main body driving means is provided.

  In addition, the main body driving unit is a driving member of an image forming unit provided in the image forming apparatus.

  Further, the drive member is a shaft for rotating the image carrier.

  The drive member is a shaft that rotationally drives the cleaning roller.

  Further, the driving member is a shaft for rotating the developing roller.

  The flywheel fixed to the shaft that rotationally drives the image carrier is provided with a striking portion that gives an impact to the pipe member.

  Further, the hitting portion is a protrusion protruding toward the pipe member.

  Moreover, the said hit | damage part decided to give a hit via the buffer member with respect to the said pipe member.

  According to the configuration of the present invention, since the pipe member vibration means for vibrating the pipe member using the main body driving means of the image forming apparatus is provided, the inner wall of the pipe that causes toner blocking by the vibration. The toner can be prevented from adhering to the toner. For example, if the pipe member is provided with a portion where the toner is transported by the action of gravity, it is not necessary to use a transport coil for the entire area from the toner carry-in port to the toner carry-out port. Therefore, since the length of the transport coil can be made relatively short, the generation of abnormal noise such as friction noise at the bent portion of the pipe member, the increase in the weight of the transport coil itself, the useless load applied to the pipe member, and the time when the image forming apparatus is driven It is possible to prevent problems such as an increase in power consumption. At the same time, it is possible to reduce the component cost. Furthermore, since the vibration of the pipe member is performed using the existing main body driving means in the image forming apparatus, it is not necessary to prepare a separate driving means, and the weight and power consumption can be further reduced.

  Further, since the main body driving means is a driving member of the image forming unit provided in the image forming apparatus, the driving member of the image forming unit adjacent to the transport of the toner collected from the surface of the image carrier is connected to the pipe. It can be used for excitation of. As a result, the pipe member oscillating means for preventing toner blocking can be easily configured without requiring a complicated mechanism.

  In addition, since the driving member is a shaft for rotating the image carrier, the pipe member for conveying the toner can be vibrated with the rotation of the image carrier, which is very convenient. During the rotation of the image carrier, that is, while the toner can be consumed, the vibration of the pipe member that conveys the toner is continued, and toner blocking can be reliably prevented.

  Further, since the driving member is a shaft for rotating the cleaning roller, the pipe member for conveying toner can be vibrated with the rotation of the cleaning roller, which is very convenient. During the rotation of the cleaning roller, that is, while the toner can be consumed, the vibration of the pipe member that transports the toner is continued, and toner blocking can be reliably prevented.

  In addition, since the driving member is a shaft for rotating the developing roller, the pipe member for conveying the toner can be vibrated with the rotation of the developing roller, which is very convenient. Further, while the developing roller rotates, that is, while the toner can be consumed, the vibration of the pipe member that conveys the toner is continued, and toner blocking can be reliably prevented.

  In addition, since the flywheel fixed to the shaft for rotating the image carrier is provided with a striking portion that gives an impact to the pipe member, a flywheel provided in advance to stabilize the rotation of the image carrier is used. It can be used to vibrate the pipe member. Thereby, it is not necessary to newly provide a member for vibrating the pipe member on the shaft for rotationally driving the image carrier, so that an increase in weight and an increase in cost can be avoided.

  In addition, since the striking part is a protrusion that protrudes toward the pipe member, the pipe member can be vibrated by the impact whenever the flywheel rotates and the protrusion collides with the pipe member. It is. Thereby, a pipe member vibration means can be obtained easily.

  Moreover, since the hit | damage part decided to give a hit with respect to a pipe member via a buffer member, it can suppress that a pipe member receives a direct impact. Therefore, since an unnecessary load is not applied to the pipe member, it is possible to prevent the pipe member from being damaged and to extend the life.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  First, an outline of the structure of an image forming apparatus according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a vertical sectional front view of the image forming apparatus A. FIG. The image forming apparatus A is a multifunction machine having a copying function and a printer function. The image forming apparatus A shown in the present embodiment relates to a monochrome developing device, but may naturally be related to color development.

  The image forming apparatus A includes a sheet feeding unit having a plurality of sheet feeding cassettes 14 attached to the lower part thereof, and a duplex unit 13 is disposed above the sheet feeding unit. Above the duplex unit 13, an image forming unit 12 and a fixing device 3 are provided. Further, an image reading unit 6 and the like are provided at the upper portion thereof, and a scanner unit 22 for reading a document image is disposed. Above the scanner unit 22, an original is automatically fed by an automatic document feeder (hereinafter referred to as ADF) 5. A mounting portion 36 is attached.

  In the image forming unit 12, an image forming unit 17 in which a charging device 16, an exposure device 10, a developing device 11, and a cleaning device 15 are disposed around the photosensitive drum 20 is provided. The photosensitive drum 20 has a photosensitive layer formed on the surface of an aluminum cylinder having a diameter of 84 mm, for example, and is driven to rotate clockwise in FIG. The charging device 16 charges the surface of the photosensitive drum 20 to several hundred volts by corona discharge. The exposure device 10 includes an LED array head and a selfoc lens, and is disposed downstream of the charging device 16 in the rotational direction of the photosensitive drum 20.

  A transfer device 19 is disposed below the photosensitive drum 20 so as to face the drum. The transfer device 19 is provided with a transfer belt 18, and the transfer belt 18 is pressed against the photosensitive drum, and a transfer nip portion is formed to transfer the toner image through the transfer paper. The transfer belt 18 rotates at the same speed as the peripheral speed of the photosensitive drum 20. Note that the transfer device 19 of the image forming apparatus A uses a transfer belt 18, but this can be replaced by a transfer roller.

  Further, a display operation unit 4 such as a liquid crystal touch panel is disposed on the upper surface of the main body of the image forming apparatus A. The user can perform various operations such as selection of an image quality mode, selection of which one of a plurality of loaded paper cassettes 14 is used, and start of image reading by the display operation unit 4.

  Next, a process when the document placed on the document placement unit 36 is read by the image reading unit 6 will be described.

  The document image light guided by the mirror from the image reading unit 6 is incident on the CCD 7, where it is A / D converted and input to the image processing unit 8 as digital image data (image data of the document). The image data of the document is subjected to predetermined image processing in the image processing unit 8, and the image data after the image processing is input to the exposure device control means 9. Then, the exposure apparatus control means 9 controls the exposure apparatus 10 so that the surface of the photosensitive drum 20 is exposed according to the image data after the image processing. The surface of the photosensitive drum 20 is uniformly charged by the charging device 16 with a predetermined polarity and potential, and the exposure device 10 exposes the potential of the irradiated portion to light attenuation to form an electrostatic latent image of the original image. .

  In the developing device 11, the developing roller rotates, and the magnetic brush provided on the surface of the developing roller contacts the surface of the photosensitive drum 20. As a result, a charged toner is attached to the electrostatic latent image on the surface of the photosensitive drum 20 to form a toner image. This toner image is transferred by the transfer device 19 to the transfer paper conveyed from the paper feed cassette 14 at a transfer nip portion formed between the photosensitive drum 20 and the transfer belt 18.

  Further, in the cleaning device 15 disposed on the downstream side of the transfer device 19, the toner remaining on the surface of the photosensitive drum 20 is scraped off by a fur brush, a blade, or the like (not shown), and the inside of the cleaning device 15. Temporarily stored. The stored residual toner is recovered in the toner recovery tank 34 or the developing tank 11a of the developing device 11 through a toner conveyance path X shown in FIGS. Details of the toner recovery mechanism will be described later.

  The transfer paper on which the toner image is transferred by the transfer device 19 is conveyed to the fixing device 3 provided on the downstream side in the transport direction. The transfer paper passes between the fixing roller 1 of the fixing device 3 and the pressure roller 2 facing the fixing roller 3, and the toner is melted and fixed by the heat of the fixing roller 1 having a heater inside. The transfer paper on which the toner image is fixed by the fixing device 3 is sent out to the transfer paper processing device B side.

  Next, the toner transport path X for collecting toner and the pipe member vibration means provided in the image forming apparatus according to the first embodiment of the present invention will be described in detail with reference to FIGS. 2 is a schematic front view showing the toner conveyance path X and the pipe member vibration means, and FIG. 3 is a schematic perspective view showing the periphery of the pipe member vibration means in FIG. Here, the toner conveyance path X is an example of a toner conveyance path included in the image forming apparatus A, and is a path for conveying the collected toner from the cleaning device 15 described with reference to FIG. 1 to the toner collection tank 34. .

  As shown in FIG. 2, the toner conveyance path X includes an outlet of a cleaning device 15 that cleans residual toner on the surface of the photosensitive drum 20, and a toner from which the toner cleaned by the cleaning device 15 is collected and stored. The recovery tank 34 is connected. The toner conveyance path X includes a hollow pipe-shaped pipe member 32 that connects the cleaning device 15 and the toner recovery tank 34, a conveyance screw 38 that sends residual toner from the cleaning device 15 to the pipe member 32, and a horizontal direction of the pipe member 32. A conveyance coil 33 that is provided only in the portion Z and conveys the toner by rotating in the pipe member 32 and a coil gear 35 that rotates the conveyance coil 33 are provided. The pipe member 32 and the conveying screw 38 are made of synthetic resin, and the conveying coil 33 is made of a stainless steel wire for springs.

  The pipe member vibration means includes a flywheel 30 and a protrusion 31 that is a striking portion. As shown in FIG. 3, the flywheel 30 is fixed to a rotating shaft 37 that is a driving member of the photosensitive drum 20 provided in the image forming unit 12 of the image forming apparatus A, and rotates the photosensitive drum 20 by its inertia. This is to prevent unevenness. Power is transmitted to the flywheel 30 by a photosensitive drum gear 36 from a driving unit (not shown), and the flywheel 30 rotates together with the photosensitive drum 20. This driving means is one of main body driving means provided in the image forming apparatus A. The flywheel 30 is made of iron. On the surface of the flywheel 30, a single protrusion 31 is provided as a striking portion that impacts and vibrates the pipe member 32 by colliding with the vertical portion Y of the pipe member 32. The protrusion 31 is formed of a screw or the like, for example, and protrudes from the surface of the flywheel 30 toward the pipe member.

  Hereinafter, the toner conveyance, the prevention of toner blocking, and other effects in the toner conveyance path X will be described.

  Toner remaining on the surface of the photosensitive drum 20 (hereinafter simply referred to as toner) is scraped off from the photosensitive drum 20 by a fur brush, a blade, or the like (not shown) and temporarily stored in the cleaning device 15. The The stored toner is fed into the pipe member 32 little by little by the rotation of the conveying screw 38.

  As shown in FIG. 2, the toner sent from the cleaning device 15 to the pipe member 32 first passes through the vertical portion Y of the pipe member 32 and is conveyed to the horizontal portion Z by free fall of the toner using gravity.

  However, in the vertical portion Y of the pipe member 32, the toner is transported by utilizing the free fall of the toner, so that the toner is caught on the inner wall of the vertical portion Y of the pipe member 32, that is, the toner adheres to the inner wall. The possibility of causing blocking is high. Therefore, the protrusion 31 provided on the flywheel 30 is caused to collide with the vertical portion Y of the pipe member 32. As a result, an impact is applied to the vertical portion Y of the pipe member 32 to vibrate, and the toner adhering to the inner wall of the pipe member 32 is dropped toward the horizontal portion Z of the pipe member 32. Then, the toner dropped to the horizontal portion Z of the pipe member 32 is transported to the toner recovery tank 34 by the transport coil 33.

  In this manner, the pipe member 32 is vibrated by using the main body driving means of the image forming apparatus A. Therefore, by vibrating, the inner wall of the pipe member 32 that causes toner blocking is provided. Toner adhesion can be prevented. Further, by providing the pipe member 32 with the vertical portion Y that is a portion where the toner is transported by the action of gravity, it is not necessary to use the transport coil 33 from the toner carry-in port to the toner carry-out port. Therefore, since the length of the transfer coil 33 can be made relatively short, the generation of abnormal noise such as frictional noise at the bent portion of the pipe member 32, the increase in the weight of the transfer coil 33 itself, a useless load applied to the pipe member 32, and image formation. It is possible to prevent the occurrence of a problem such as an increase in power consumption when driving apparatus A. At the same time, it is possible to reduce the component cost. Furthermore, since the vibration of the pipe member 32 is performed using the existing main body driving means in the image forming apparatus A, it is not necessary to prepare a separate driving means, and the weight and power consumption can be further reduced.

  Further, since the main body driving unit is a driving member of the image forming unit 12 provided in the image forming apparatus A, the image forming unit adjacent to the transport of the toner collected from the surface of the photosensitive drum 20 as the image carrier. Twelve drive members can be used for exciting the pipe member 32. As a result, the pipe member oscillating means for preventing toner blocking can be easily configured without requiring a complicated mechanism.

  Further, since the driving member is the rotating shaft 37 that rotates and drives the photosensitive drum 20 that is an image carrier, the pipe member 32 that conveys toner can be vibrated with the rotation of the photosensitive drum 20. It is very convenient. Then, while the photosensitive drum 20 rotates, that is, while the toner can be consumed, the vibration of the pipe member 32 that conveys the toner is continued, and toner blocking can be reliably prevented.

  Since the flywheel 30 fixed to the shaft 37 for rotating the photosensitive drum 20 is provided with a striking portion that gives an impact to the pipe member 32, it is provided in advance to stabilize the rotation of the photosensitive drum 20. The pipe member 32 can be vibrated using the flywheel 30. As a result, it is not necessary to newly provide a member for vibrating the pipe member 32 on the shaft 37 of the photosensitive drum 20, so that an increase in weight and an increase in cost can be avoided.

  In addition, since the striking portion is the protrusion 31 protruding toward the pipe member 32, the flywheel 30 rotates and the pipe member 32 is vibrated by the impact each time the protrusion 31 collides with the pipe member 32. Is possible. Thereby, a pipe member vibration means can be obtained easily.

  The first embodiment is an example in which the pipe member 32 is constituted by a series of continuous pipes. When the pipe member 32 is integrated as described above, the entire pipe member 32 is added when vibrating. I have to shake it. However, in order to prevent the toner from adhering to the inner wall of the pipe member 32, it is sufficient to vibrate only the vertical portion Y of the pipe member 32. Therefore, when the entire pipe member 32 is vibrated, the power for vibration is increased. Is wasted.

  Therefore, an image forming apparatus according to the second embodiment of the present invention, in which the vertical portion Y of the pipe member 32 is separated from the horizontal portion Z and can be vibrated independently, will be described with reference to FIG. FIG. 4 is a schematic front view of the pipe member 32 in which the movable portion and the fixed portion of the vertical portion Y are connected by a flexible member. Since the basic configuration of this embodiment is the same as that of the first embodiment, the description of the drawings and the description of the components common to the first embodiment will be omitted.

  As shown in FIG. 4, in the vertical portion Y of the pipe member 32, the movable portion C <b> 1 and the fixed portions D <b> 1 and D <b> 2 are flexibly connected by the bellows member 40. In this case, when the protrusion 31 of the flywheel 30 collides with a predetermined position of the movable part C1, the movable part C1 is vibrated by an impact, but the impact is absorbed by the bellows member 40, so that the fixed part D1 and The vibration is not transmitted to D2. Thereby, most of the impact applied to the vertical portion Y of the pipe member 32 is applied only to the movable portion C1, and is hardly transmitted to the fixed portions D1 and D2. The toner can be prevented from adhering to the inner wall of the pipe member 32. Therefore, the loss of power is reduced, and the pipe member 32 is not subjected to an excessive burden due to impact.

  Next, as in the second embodiment of the present invention, a part of the vertical portion Y of the pipe member 32 that is movable is shown as an image forming apparatus according to the third embodiment of the present invention. 5 will be described. FIG. 5 is a schematic front view of the pipe member 32 in which the movable portion and the fixed portion of the vertical portion Y are connected in a fitted state. Since the basic configuration of this embodiment is the same as that of the first and second embodiments, the description of the drawings and the description of components common to these embodiments are omitted. And

  As shown in FIG. 5, in the vertical part Y of the pipe member 32, the movable part C2 and the fixed parts D3 and D4 are connected in a fitted state. The fixing portions D3 and D4 are fixed to the main body of the image forming apparatus A. In this case, since there is no resistance by the bellows member 40 used in the second embodiment, the vertical portion Y can be vibrated with an increasingly smaller excitation force. Accordingly, power loss and load on the pipe member 32 can be further reduced. In addition, it is possible to prevent the toner from leaking by increasing the fitting diameter as it goes downward in the vertical portion Y. Moreover, you may comprise in the funnel type (taper type) which tapers each pipe member downward.

  Next, the detailed structure of the pipe member vibration means provided in the image forming apparatus according to the fourth embodiment of the present invention will be described with reference to FIGS. FIG. 6 is a schematic front view showing the periphery of the image forming unit, and FIG. 7 is also a schematic partial top view showing only the back side portion of the image forming apparatus. FIG. 8 is a schematic perspective view showing the pipe member vibration means. Since the basic configuration of this embodiment is the same as that of the first to third embodiments, the description of the drawings and the description of components common to these embodiments are omitted. To do.

  As shown in FIGS. 6 and 7, the cleaning device 15 includes a cleaning roller 50. The cleaning roller 50 is provided in contact with the photosensitive drum 20. The cleaning roller 50 has substantially the same axial length as the photosensitive drum 20, is urged by an elastic member such as a spring (not shown), and is pressed against the photosensitive drum 20.

  In order to perform the cleaning efficiently, it is necessary to relatively move the peripheral surfaces of the cleaning roller 50 and the photosensitive drum 20 relative to each other. Therefore, the cleaning roller 50 is reverse to the rotation direction of the photosensitive drum 20 with respect to the rotation axis so that the peripheral speed of the cleaning roller 50 is about 15 to 20% faster than the peripheral speed of the photosensitive drum 20 by a driving unit (not shown). It is rotated in the direction. This driving means is one of the main body driving means provided in the image forming apparatus A, and transmits power through the cleaning roller gear 51 shown in FIG. In this way, the toner remaining on the surface of the photosensitive drum 20 is removed and cleaned by the cleaning roller 50. The toner removed from the surface of the photosensitive drum 20 is collected in the housing 52.

  A pipe member 32 is provided on the back surface of the cleaning device 15. The pipe member 32 includes a vertical portion Y that protrudes horizontally at a predetermined length and then extends downward. The toner in the housing 52 is conveyed to the upper end of the vertical portion Y by the conveying screw 53.

  A flywheel 60 is provided on the further back side of the pipe member 32. The flywheel 60 is fixed to the rotating shaft 54 of the cleaning roller 50 protruding from the housing 52 of the cleaning device 15. As shown in FIGS. 7 and 8, the front surface of the flywheel 60, that is, the surface on the pipe member 32 side collides with the vertical portion Y of the pipe member 32, so that the pipe member 32 is impacted and excited. One protrusion 61 is provided as a hitting part. The protrusion 61 protrudes in a hemispherical shape from the surface of the flywheel 60. The flywheel 60 and the protrusion 61 constitute a pipe member vibration means.

  In this way, in the pipe member oscillating means, the drive member used for oscillating the pipe member 32 is the rotating shaft 54 that drives the cleaning roller 50 to rotate. It is possible to vibrate the pipe member 32 that conveys the gas. Further, while the cleaning roller 50 rotates, that is, while the toner can be consumed, the vibration of the pipe member 32 that conveys the toner is continued, and toner blocking can be reliably prevented.

  Next, a detailed configuration of the pipe member vibration means provided in the image forming apparatus according to the fifth embodiment of the present invention will be described with reference to FIGS. 9 and 10. FIG. 9 is a model front view showing the periphery of the image forming unit, and FIG. 10 is also a model partial top view showing only the back side portion of the image forming apparatus. Since the basic configuration of this embodiment is the same as that of the first to fourth embodiments, the description of the drawings and the description of components common to these embodiments are omitted. To do.

  As shown in FIGS. 9 and 10, the developing device 11 includes a developing roller 70. The developing roller 70 has substantially the same axial length as that of the photosensitive drum 20 and is provided so as to contact the photosensitive drum 20. The developing roller 70 is rotated in a direction opposite to the rotation direction of the photosensitive drum 20 by a driving unit (not shown). This driving means is one of main body driving means provided in the image forming apparatus A, and transmits power via a driven gear (not shown).

  A bias having the same polarity as the charging polarity of the photosensitive drum 20 is applied to the developing roller 70. The developing roller 70 charges toner as a developer and supplies the toner to the surface of the photosensitive drum 20 to develop the electrostatic latent image. As the toner, a magnetic or non-magnetic one-component toner, or a two-component developer obtained by mixing a magnetic carrier and an insulating toner is used. In addition, in order to clean the surface of the photosensitive drum 20 by polishing, a small amount of powder of titanium oxide, alumina or the like may be mixed into the toner as an abrasive.

  A flywheel 80 is provided on the further back side of the pipe member 32 provided on the back surface portion of the cleaning device 15. The flywheel 80 is fixed to a rotating shaft 81 that is rotatably supported by the main body of the image forming apparatus A. The rotation shaft 81 is connected to the rotation shaft 71 of the developing roller 70 via a timing belt 72. As a result, the flywheel 80 rotates according to the rotation of the developing roller 70. The front surface of the flywheel 80, that is, the surface on the pipe member 32 side, is provided with one protrusion 82 that is a striking portion that impacts and vibrates the pipe member 32 by colliding with the vertical portion Y of the pipe member 32. It has been. The protrusion 82 protrudes hemispherically from the surface of the flywheel 80. The flywheel 80 and the protrusion 82 constitute pipe member vibration means.

  In this way, in the pipe member oscillating means, the driving member used for oscillating the pipe member 32 is the rotating shaft 71 that drives the developing roller 70 to rotate. It is possible to vibrate the pipe member 32 that conveys the gas. While the developing roller 70 rotates, that is, while the toner can be consumed, the vibration of the pipe member 32 that transports the toner is continued, and toner blocking can be reliably prevented.

  Next, the detailed structure of the pipe member vibration means provided in the image forming apparatus according to the sixth embodiment of the present invention will be described with reference to FIG. FIG. 11 is a schematic perspective view showing the pipe member vibration means. Since the basic configuration of this embodiment is the same as that of the first to fifth embodiments, the description of the drawings and the description of components common to these embodiments are omitted. To do.

  As shown in FIG. 11, the pipe member vibration means includes a flywheel 90, a recess 91, and a protrusion 92. One recess 91 is provided on the front surface of the flywheel 90, that is, on the surface on the pipe member 32 side, and is recessed in a hemispherical shape toward the inside of the flywheel 90. On the other hand, one projection 92 is provided at a position corresponding to the recess 92 on the flywheel 90 side of the vertical portion Y outer surface of the pipe member 32. The protrusion 92 has a size that fits in the recess 91. The flywheel 90 and the pipe member 32 are arranged so that the protrusion 92 is always lightly pressed against the surface of the flywheel 90.

  When the flywheel 90 rotates, the protrusion 92 is accommodated in the recess 91 when the recess 91 comes to the position of the protrusion 92 by rotation. Therefore, the vertical contact Y between the tip of the projection 92 and the flywheel 90 surface is suddenly released, and the vertical portion Y of the pipe member 32 is vibrated.

  Thus, as in the present embodiment, the pipe member oscillating means is configured by the flywheel 90, the concave portion 91 provided on the surface, and the protrusion 92 that fits in the concave portion 91. It is possible to obtain the same effect as in the above embodiment. That is, it is possible to cause the vertical part Y of the pipe member 32 to vibrate and vibrate, and to drop the toner adhering to the inner wall of the pipe member 32 toward the horizontal part Z (see FIG. 2) of the pipe member 32.

  Next, the detailed structure of the pipe member vibration means provided in the image forming apparatus according to the seventh embodiment of the present invention will be described with reference to FIG. FIG. 12 is a schematic perspective view showing the pipe member vibration means. Since the basic configuration of this embodiment is the same as that of the first to sixth embodiments, the description of the drawings and the description of the components common to these embodiments are omitted. To do.

  As shown in FIG. 12, the pipe member vibration means includes a flywheel 100, a step 101, and a stick 102. One step 101 is provided on the outer peripheral surface of the flywheel 100. At the position of the step 101, the radius with respect to the outer peripheral surface of the flywheel 100 changes abruptly. On the other hand, one stick 102 is provided on the flywheel 100 side of the outer surface of the vertical portion Y of the pipe member 32 at a position where the outer peripheral surface contacts the outer peripheral surface of the flywheel 100. The stick 102 has such a length that its tip reaches the back surface of the flywheel 100. The flywheel 100 and the pipe member 32 are arranged so that the stick 102 always comes in light contact with the outer peripheral surface of the step 101 where the radius of the flywheel 100 is the smallest.

  When the flywheel 100 rotates, the pressure toward the radially outer side of the stick 102 gradually increases as the radius of the outer peripheral surface of the flywheel 100 increases until the step 101 reaches the position of the stick 102 due to the rotation. Receive. Then, the vertical portion Y of the pipe member 32 is vibrated by receiving an impact when the pressure received by the stick 102 is suddenly released at the step 101.

  Thus, as in the present embodiment, the pipe member vibration means is configured by the flywheel 100, the step 101 provided on the outer peripheral surface, and the stick 102 engaged with the step 101. Even if it exists, it is possible to acquire the effect similar to the said embodiment. That is, it is possible to cause the vertical part Y of the pipe member 32 to vibrate and vibrate, and to drop the toner adhering to the inner wall of the pipe member 32 toward the horizontal part Z (see FIG. 2) of the pipe member 32.

  Next, the detailed configuration of the pipe member vibration means provided in the image forming apparatus according to the eighth embodiment of the present invention will be described with reference to FIG. FIG. 13 is a schematic side view showing the pipe member vibration means. Since the basic configuration of this embodiment is the same as that of the first to seventh embodiments, the description of the drawings and the description of components common to these embodiments are omitted. To do.

  As shown in FIG. 13, a protrusion 61 as a hitting portion is provided on the surface of the flywheel 60 on the pipe member 32 side. On the other hand, a buffer member 110 is provided at a position corresponding to the protrusion 61 of the flywheel 60 in the vertical portion Y of the pipe member 32. The buffer member 110 is a bowl-shaped member protruding from the pipe member 32 and is made of synthetic resin. One end of the buffer member 110 is fixed to the pipe member 32, and the other end is a free end extending downstream in the rotational direction of the flywheel 60.

  When the flywheel 60 rotates, the protrusion 61 rides on the outer surface of the buffer member 110 by rotation, and the buffer member 110 receives pressure in a direction away from the flywheel 60. And the protrusion 61 passes through the location of the buffer member 110, the pressure which the buffer member 110 receives is suddenly cancelled | released, it receives an impact, and the free end part of the buffer member 110 is vibrated. Thereby, the vertical part Y of the pipe member 32 vibrates gently.

  Thus, since the protrusion 31 which is a hit | damage part gives a hit with respect to the pipe member 32 via the buffer member 110, it can suppress that the pipe member 32 receives a direct impact. Therefore, since an extra load is not applied to the pipe member 32, the pipe member 32 can be prevented from being damaged and the life can be extended.

  In any case of the first to eighth embodiments, the flywheel is used as the pipe member vibration means, but the pipe member 32 is not limited to the flywheel as the vibrator is vibrated. Alternatively, other rotation mechanisms or the like may be used. In each of the above-described embodiments, the number of locations where impacts such as protrusions are applied has been described as being one, but a plurality of locations may be provided.

  For example, as shown in FIG. 2, the protrusion 31 makes contact with the pipe member 32 in the vertical plane by the rotation of the flywheel 30, but the arrangement of the flywheel 30 and the protrusion 31 and the pipe member 32 is changed. Thus, the same effect can be obtained even if contact is made in a horizontal plane.

  Further, the pipe member 32 of the toner conveyance path X has a vertical portion Y and a horizontal portion Z, and in the horizontal portion Z, the conveyance coil 33 is rotationally driven to convey the toner. The shape of the vertical portion Y is not necessarily vertical as long as it extends in the vertical direction, and may be inclined. Further, the toner conveyance of the horizontal portion Z is not limited to the one using the conveyance coil 33. The operation and effect of the present invention are the same as long as the toner can be conveyed without using the conveyance coil 33. Can get to. That is, the present invention can be applied to the case where the pipe member 32 extends in the vertical direction over the entire length.

  As the toner transport path X, an example in which the recovered toner is transported from the cleaning device 15 included in the image forming apparatus A to the toner recovery tank 34 is described. However, this is merely an example of the embodiment. For example, the toner transport path in the case where the toner is transported from a toner container such as a toner cartridge to another toner container (for example, a developing tank in the developing device) is also described. The invention is equally applicable. Further, the image forming apparatus A may adopt a toner recycling system that does not emit waste toner, that is, returns all collected toner to the developing tank, or may store the collected toner in a collection tank.

  Although the embodiment of the present invention has been described above, various modifications can be made without departing from the spirit of the present invention.

  The present invention can be used in general image forming apparatuses using powdered toner as a developer.

1 is a vertical sectional front view of an image forming apparatus A according to an embodiment of the present invention. 2 is a schematic front view showing a toner conveyance path X and a pipe member vibration unit provided in the image forming apparatus A according to the first embodiment of the present invention. FIG. It is a model perspective view which shows the pipe member vibration means periphery of FIG. It is a model front view of the pipe member 32 of the image forming apparatus A which concerns on the 2nd Embodiment of this invention. It is a model front view of the pipe member 32 of the image forming apparatus A which concerns on the 3rd Embodiment of this invention. It is a model front view which shows the image formation part periphery of the image forming apparatus A which concerns on the 4th Embodiment of this invention. FIG. 7 is a schematic partial top view showing the image forming unit in FIG. 6, in which only the back side portion of the image forming apparatus is depicted. It is a model perspective view which shows the pipe member vibration means of FIG. It is a model front view which shows the image formation part periphery of the image forming apparatus A which concerns on the 5th Embodiment of this invention. FIG. 10 is a schematic partial top view showing the image forming unit in FIG. 9, in which only the back side portion of the image forming apparatus is drawn. It is a model perspective view which shows the pipe member vibration means of the image forming apparatus A which concerns on the 6th Embodiment of this invention. It is a model perspective view which shows the pipe member vibration means of the image forming apparatus A which concerns on the 7th Embodiment of this invention. It is a model side view which shows the pipe member vibration means of the image forming apparatus A which concerns on the 8th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 8 Image processing part 11 Developing device 12 Image forming part 15 Cleaning device 18 Transfer belt 19 Transfer device 20 Photosensitive drum 30 Flywheel 31 Protrusion (striking part)
32 Pipe member 33 Conveying coil 34 Toner recovery tank 37 Rotating shaft 40 Bellows member 50 Cleaning roller 54 Rotating shaft 60, 80 Flywheel 61, 82 Protrusion (striking portion)
70 Developing roller 71 Rotating shaft 90 Flywheel 91 Concave 92 Protrusion 100 Flywheel 101 Step 102 Stick 110 Buffer member C1, C2 Pipe member movable part D1, D2, D3, D4 Pipe member fixed part Y Pipe member vertical part Z Horizontal part of pipe member

Claims (8)

In an image forming apparatus comprising a main body driving means for driving the main body of the image forming apparatus and a pipe member that conveys toner and that partially or entirely extends in the vertical direction.
An image forming apparatus comprising: a pipe member vibration unit that vibrates the pipe member using the main body driving unit.   The image forming apparatus according to claim 1, wherein the main body driving unit is a driving member of an image forming unit provided in the image forming apparatus.   The image forming apparatus according to claim 2, wherein the driving member is a shaft that rotationally drives the image carrier.   The image forming apparatus according to claim 2, wherein the driving member is a shaft that rotationally drives the cleaning roller.   The image forming apparatus according to claim 2, wherein the driving member is a shaft that rotationally drives the developing roller.   The image forming apparatus according to claim 3, wherein a striking unit that applies an impact to the pipe member is provided on a flywheel fixed to a shaft that rotationally drives the image carrier.   The image forming apparatus according to claim 6, wherein the hitting portion is a protrusion protruding toward the pipe member.   The image forming apparatus according to claim 6, wherein the hitting portion hits the pipe member via a buffer member.

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