JP4380780B2 - Development device regeneration method - Google Patents

Description

  The present invention relates to a reproducing method for a developing device used in a laser printer or the like.

  2. Description of the Related Art Conventionally, a developing cartridge filled with toner is detachably attached to an electrophotographic image forming apparatus such as a laser printer.

  Such a developing cartridge is defined in a filling chamber and a developing chamber. The filling chamber is provided with an agitator that is filled with toner and is driven to rotate. The developing chamber is provided with a supply roller and a developing roller that are disposed to face each other in contact with each other, and a layer thickness regulating blade that is in pressure contact with the surface of the developing roller.

  Then, the developing cartridge is mounted on the laser printer, and when the power from the laser printer is input by gear connection or the like, the toner filled in the filling chamber is conveyed into the developing chamber by the rotational drive of the agitator. . In the developing chamber, the toner is supplied to the developing roller by the rotation of the supply roller. At this time, the toner is frictionally charged between the supply roller and the developing roller. Further, the toner supplied on the surface of the developing roller enters between the layer thickness regulating blade and the developing roller as the developing roller rotates, and is carried on the surface of the developing roller as a thin layer having a certain thickness. The

Such a developing cartridge is disposed in a laser printer so that the developing roller and the photosensitive drum face each other. When the toner carried as a thin layer on the surface of the developing roller is opposed to the photosensitive drum, the electrostatic latent image formed on the surface of the photosensitive drum is developed to form a visible image. Then, the visible image is transferred onto the sheet by the transfer roller, whereby a predetermined image is formed on the sheet. Further, as described above, such a developing cartridge is used by being mounted on the laser printer. As a result, the toner in the filling chamber is consumed. When the remaining amount of toner decreases, the laser printer displays toner empty and prompts the user to replace the developing cartridge, so that the user removes the used developing cartridge and installs a new developing cartridge. I am doing so.

  However, in recent years, from the viewpoint of environmental protection, a technique for regenerating (recycling) a used developing cartridge without discarding the used developing cartridge as it is is spreading.

  For example, as described in Japanese Patent Application Laid-Open No. 2003-263029, a used developing cartridge is once collected, and this used developing cartridge is used for suspension polymerization used at the time of use before the developing cartridge. A toner that has a lower fluidity than the toner and has a higher fluidity than the pulverized toner that has not been spheroidized, that is, an emulsion polymerization toner or a smaller amount of toner than the suspension polymerization toner used in the previous use. A technique is known in which a suspension polymerization toner containing an additive is refilled and reused.

  However, the rotating shafts of the developing roller and the supply roller and the bearings that rotatably support those rotating shafts are gradually worn away due to the use of the developing cartridge, and a scrap is generated. The rotating shaft and the bearings As a result, the torque applied to the gear fixed to the rotating shaft increases. As the wear further progresses, the rotating shaft is shaken, and the torque further increases.

  In addition, the rotating shaft provided integrally with the developing cartridge and the gear rotatably attached to the rotating shaft also wear with the use of the developing cartridge, and as a result, the torque applied to the gear. Will increase.

  Therefore, if the rotation shafts and bearings continue to be used as they are after the development cartridge has been regenerated, the torque applied to the gear connected to the rotation shaft will increase compared to the previous use, and the gear teeth will jump. May occur.

  In particular, when the technology described in Japanese Patent Application Laid-Open No. 2003-263029 is used in the regeneration of the developing cartridge, the toner is developed by refilling with toner having lower fluidity than the toner used at the previous use. Resistance when the toner passes between the roller and the supply roller or between the developing roller and the layer thickness regulating blade is increased. Further, the resistance from the toner applied to the agitator or the like also increases. As a result, the torque applied to the gear that drives the developing cartridge that is refilled with toner and reused increases, and the risk of gear tooth jumping and damage after regeneration increases.

  As described in Japanese Patent Application Laid-Open No. 11-327286, in a driving device that charges toner by friction between a supply roller and a developing roller, a gear to which high torque is applied is made of a resin material containing glass fiber. The technology to do is known. According to this technique, even when a high load is applied to the gear, it is possible to prevent the gear teeth and gear teeth from being damaged.

  However, a new developing cartridge is not always regenerated after being used. The reasons for this are as follows. (1) When a developing cartridge that has never been regenerated is damaged due to an accident, it is discarded without being regenerated. (2) A user accidentally discards a developing cartridge that has never been regenerated. (3) Some users prefer to use new developer cartridges that have never been regenerated.

  Therefore, in the production of a new and unreproduced developing cartridge, it is difficult to recycle, like a resin material containing glass fiber, the manufacturing process is complicated, and the manufacturing cost is high. Is not preferable. Furthermore, there is a problem that the manufacturing process becomes unnecessarily complicated and the manufacturing cost increases.

The present invention has been made to solve the above-described problems, and prevents the gear from skipping during use after regeneration in the regeneration of the developing cartridge, and further, a new development that has never been regenerated. The purpose of manufacturing the cartridge is to eliminate the need for a gear having a high environmental load, a complicated manufacturing process, and a high manufacturing cost.
JP 2003-263029 A JP-A-11-327286

  2. A reproduction method for a developing device according to claim 1, wherein a developer carrying member for carrying the developer and a gear mechanism having a plurality of gears for transmitting the driving force input from the image forming apparatus main body to the developer carrying member. A developing device regeneration method comprising: a rotation portion that is slidable with respect to the gear and that rotatably supports the gear, and is detachable from the image forming apparatus main body. And a step of sandwiching a sliding member between the gear and a surface facing the peripheral surface of the rotating shaft.

  According to the first aspect of the present invention, since the sliding member is sandwiched between the rotating shaft and the gear, it is possible to compensate for the wear of the rotating shaft and the surface facing the rotating shaft peripheral surface of the gear wear. As a result, an increase in torque applied to the gear can be prevented.

  In addition, in the production of a new developer cartridge that has not been regenerated, there is no need to use a gear that has a large environmental load, a complicated manufacturing process, and high manufacturing costs.

[Example 1]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional side view of an essential part showing an embodiment of a laser printer as an image forming apparatus to which a developing cartridge as a developing apparatus of the present invention is attached. In FIG. 1, the laser printer 1 is configured as a laser printer that forms an image by an electrophotographic method. In a main body casing 2, a feeder unit 4 for feeding a sheet 3 as a recording medium, An image forming unit 5 for forming a predetermined image on the paper 3 is provided.

  The feeder unit 4 includes a paper feed tray 6 that is detachably attached to the bottom of the main body casing 2, a paper feed mechanism unit 7 that is provided at one end of the paper feed tray 6, and a paper feed tray 6. The downstream side in the transport direction of the paper 3 with respect to the provided paper pressing plate 8 and the paper feed mechanism unit 7 (hereinafter, the upstream or downstream side in the transport direction of the paper 3 may be simply referred to as the upstream side or the downstream side in some cases. )) And a registration roller 11 provided on the downstream side of the first conveyance roller 9 and the second conveyance roller 10 in the conveyance direction of the sheet 3. Yes.

  The paper feed tray 6 has a box shape with an open upper surface capable of accommodating the sheets 3 in a stacked manner, and is detachable in the horizontal direction with respect to the bottom of the main casing 2.

  The paper feed mechanism unit 7 includes a paper feed roller 12 and a separation pad 13 that faces the paper feed roller 12. A spring 13 a is disposed on the back side of the separation pad 13, and an urging force of the spring 13 a is provided. Thus, the separation pad 13 is pressed against the paper feed roller 12.

  The sheet pressing plate 8 can stack the sheets 3 in a stacked manner, and is supported so as to be swingable at the end far from the sheet feeding roller 12, thereby moving the near end in the vertical direction. It is possible to be biased upward by a spring (not shown) from the back side. Therefore, the sheet pressing plate 8 is swung downward against the biasing force of the spring, with the end portion farther from the sheet feeding mechanism unit 7 as a fulcrum as the amount of stacked sheets 3 increases. The uppermost sheet 3 on the sheet pressing plate 8 is pressed toward the sheet feeding roller 12 by a spring (not shown) from the back side of the sheet pressing plate 8, and the sheet feeding roller 12 is rotated by the rotation of the sheet feeding roller 12. After being sandwiched between the separation pads 13, they are separated and fed one by one by their cooperation. The fed paper 3 is sent to the registration roller 11 by the first transport roller 9 and the second transport roller 10.

  The registration roller 11 is composed of a pair of rollers, and sends the paper 3 to the image forming position after a predetermined registration. The image forming position is a transfer position at which the toner image on the photosensitive drum 23 is transferred to the paper 3, that is, a contact position between the photosensitive drum 23 and the transfer roller 25 in this embodiment.

  The feeder unit 4 of the laser printer 1 further includes a multipurpose tray 14 on which sheets 3 of an arbitrary size are stacked, and a multipurpose supply for feeding the sheets 3 stacked on the multipurpose tray 14. A paper mechanism unit 15 and a multi-purpose conveyance roller 16 are provided.

  The multi-purpose paper feed mechanism 15 includes a multi-purpose paper feed roller 15a and a multi-purpose separation pad 15b facing the multi-purpose paper feed roller 15a. A spring 15c is provided on the back side of the multi-purpose separation pad 15b. The multi-purpose separation pad 15b is pressed against the multi-purpose sheet feeding roller 15a by the urging force of the spring 15c.

  The uppermost paper 3 stacked on the multi-purpose tray 14 is sandwiched between the multi-purpose paper feed roller 15a and the multi-purpose separation pad 15b by the rotation of the multi-purpose paper feed roller 15a, and then cooperates with them. Thus, the sheets are separated one by one and fed toward the registration roller 11.

  The image forming unit 5 includes a scanner unit 17, a process unit 18, a fixing unit 19, and the like.

  The scanner unit 17 is provided at an upper portion in the main body casing 2 and includes a laser light emitting unit (not shown), a polygon mirror 20 that is driven to rotate, lenses 21a and 21b, a reflecting mirror 22, and the like. As shown by the chain line, the laser beam based on the predetermined image data emitted from is passed or reflected in the order of the polygon mirror 20, the lens 21a, the reflecting mirror 22, and the lens 21b, and the photosensitive drum of the process unit 18 to be described later. The surface 23 is irradiated with high-speed scanning.

  The process unit 18 is disposed below the scanner unit 17 and is configured to be detachably attached to the main body casing 2. The process unit 18 includes a photosensitive drum 23 as an image carrier, a developing cartridge 24 as a developing device, a transfer roller 25 as a transfer unit, and a scorotron charger 37 in a drum cartridge 38. .

  The developing cartridge 24 is detachably attached to the drum cartridge 38. The developing cartridge 24 can be attached to the drum cartridge 38 even when the drum cartridge 38 is detached from the main body casing 2 of the laser printer 1 or is attached. As shown in FIG. 2, the housing 24a of the developing cartridge 24 is divided into a filling chamber 26a filled with toner as a developer and a developing chamber 26b, and the toner is supplied to the partition between them. An opening 39 is formed.

  An agitator 40 is rotatably provided in the filling chamber 26a, and is filled with a positively charged non-magnetic one-component toner. The agitator 40 includes a rotating shaft 40a rotatably supported at the center in the filling chamber 26a, a stirring blade 40b provided around the rotating shaft 40a, and a film attached to the free end portion of the stirring blade 40b. And a member 40c. Then, the rotating shaft 40a is driven to rotate by the power from the gear mechanism 59 described later, and the film member 40c scrapes up the toner in the filling chamber 26a and conveys it to the developing chamber 26b by the rotation of the stirring blade 40b. It is configured. A rotating shaft 40a of the agitator 40 is provided with a cleaner 63 for cleaning a window 62, which will be described later, on the side opposite to the stirring blade 40b.

  In the developing chamber 26b, a developing roller 27 as a developer carrying member, a layer thickness regulating blade 28 as a layer thickness regulating member, and a supply roller 29 as a supply unit are provided.

  The supply roller 29 is disposed below the toner supply port 39 so as to be rotatable in the arrow direction (clockwise). The supply roller 29 has a metal roller shaft covered with a roller made of a conductive sponge material.

  The developing roller 27 is disposed on the side of the supply roller 29 so as to be rotatable in the arrow direction (clockwise). In the developing roller 27, a metal roller shaft is coated with a roller made of a conductive elastic material. More specifically, the roller of the developing roller 27 is a conductive urethane rubber containing carbon fine particles. Alternatively, the surface of a roller made of silicone rubber is coated with a urethane rubber or silicone rubber coating layer containing fluorine. A predetermined developing bias is applied to the developing roller 27 with respect to the photosensitive drum 23. The supply roller 29 and the developing roller 27 are in contact with each other in a state where each of them is compressed to some extent.

  A layer thickness regulating blade 28 is disposed in the vicinity of the developing roller 27. The layer thickness regulating blade 28 is arranged above the developing roller 27 so as to face along the axial direction of the developing roller 27.

  This layer thickness regulating blade 28 is provided with a leaf spring member 28a and a semicircular cross-sectional pressure made of insulating silicone rubber as a contact portion that is provided at the tip of the leaf spring member 28a and contacts the developing roller 27. A portion 28b, a backup member 28c provided on the back surface of the leaf spring member 28a, and a support member 28d for supporting the rear end portion of the leaf spring member 28a on the housing 24a of the developing cartridge 24. The layer thickness regulating blade 28 is developed by the elastic force of the leaf spring member 28a pressed by the backup member 28c while the leaf spring member 28a is supported by the housing 24a by the support member 28d. It is pressed on the roller 27.

  In this way, by forming the pressing portion 28b of the layer thickness regulating blade 28 with silicone rubber, the toner can be carried on the developing roller 27 in a well charged state.

  Further, as shown in FIG. 3, the developing cartridge 24 is open on the side where the developing roller 27 is disposed in the casing 24a, and the side walls 56 of the casing 24a are open to the side of the casing 24a. A support hole 57 for mounting and supporting the roller shaft of the developing roller 27 from the side is formed. The support hole 57 is formed in a concave groove shape that is continuous from the open side end portions of the side walls 56.

  In addition, side seals 58 as seal members for preventing toner leakage at both axial ends of the developing roller 27 are attached to the inner sides of the side walls 56 adjacent to the side walls 56. The side seal 58 has a felt member stuck on a sponge member, and both end portions in the axial direction of the developing roller 27 are slidably mounted on the side seal 58. Further, similarly to the side seal 58, a lower side seal 64 for preventing toner leakage is attached to the inner side adjacent to the side seal 58.

  In FIG. 3, only one axial end portion of the developing roller 27 is shown, but the other axial end portion has the same configuration.

  Further, as shown in FIG. 4, the developing cartridge 24 includes a developing roller 27 and a side wall 56a on both side walls 56 where both ends in the axial direction of the developing roller 27 in the housing 24a are supported. A gear mechanism 59 as a drive mechanism for driving the agitator 40 is provided, and a toner cap 60 as a lid for opening and closing the filling chamber 26a is provided on the other side wall 56b side.

  In the gear mechanism 59, a developing roller driving gear 59a, a supply roller driving gear 59b, an input gear 59c, an intermediate gear 59d, and an agitator driving gear 59e are rotatably supported by a holder plate 61 supported by the side wall 56a. Here, the developing roller drive gear 59a is fixed to the developing roller 27, the supply roller drive gear 59b is fixed to the supply roller 29, and the input gear 59c meshes with the development roller drive gear 59a and the supply roller drive gear 59b. Yes. The intermediate gear 59d is a two-stage gear composed of a large intermediate gear 59dn that meshes with the input gear 59c and a small intermediate gear 59dm that meshes with the agitator drive gear 59e. The agitator drive gear 59e is connected to the rotating shaft 40a of the agitator 40. When the developing cartridge 24 is mounted on the laser printer 1 and power is input from a motor (not shown) of the laser printer 1 to the input gear 59c via the coupling 80 of the input gear 59c, the input gear 59c is engaged. The developing roller 27 and the supply roller 29 are rotationally driven via the developing roller drive gear 59a and the supply roller drive gear 59b. Further, the agitator 40 is rotationally driven through an intermediate gear 59d that meshes with the input gear 59c and an agitator drive gear 59e that meshes with the intermediate gear 59d.

  In addition, the toner cap 60 opens and closes an opening formed in the other side wall 56b, and discharges the toner used during the previous use of the developing cartridge 24 from the filling chamber 26a when refilling the toner described later. The toner to be refilled is used to supply the filling chamber 26a.

  As shown in FIG. 2, the toner in the filling chamber 26a is agitated by the rotation of the agitator 40 in the arrow direction (counterclockwise direction) and conveyed from the toner supply port 39 to the developing chamber 26b. The side wall 56 of the filling chamber 26 a is formed with a window 62 for transmitting light of a photosensor (not shown), and the window 62 is cleaned by a cleaner 63 supported by the agitator 40. The window 62 is used to detect the remaining amount of toner. When the filling chamber 26a is filled with toner, the light of the optical sensor is not transmitted and the remaining amount of toner in the filling chamber 26a decreases. The laser printer 1 transmits the light of the optical sensor and displays toner empty on an operation panel (not shown) provided in the main body casing 2.

  Next, the toner conveyed from the toner supply port 39 to the developing chamber 26b is supplied to the developing roller 27 by the rotation of the supplying roller 29. At this time, the toner is positively frictionally charged between the supplying roller 29 and the developing roller 27. Next, the toner supplied onto the developing roller 27 enters between the pressing portion 28b of the layer thickness regulating blade 28 and the developing roller 27 as the developing roller 27 rotates, and a thin layer having a constant thickness is obtained. Is reliably carried on the developing roller 27.

  As shown in FIG. 1, the photosensitive drum 23 is disposed at a side position of the developing roller 27 so as to be able to rotate in the arrow direction (counterclockwise direction) so as to face the developing roller 27. The photosensitive drum 23 is formed of a positively chargeable photosensitive layer having a drum body grounded and a surface portion made of polycarbonate or the like.

  The scorotron charger 37 is disposed above the photosensitive drum 23 at a predetermined interval so as not to contact the photosensitive drum 23. The scorotron charger 37 is a positively charged scorotron charger that generates corona discharge from a charging wire such as tungsten, and is configured to uniformly charge the surface of the photosensitive drum 23 to a positive polarity. ing.

  The surface of the photosensitive drum 23 is first uniformly charged positively by the scorotron charger 37 as the photosensitive drum 23 rotates, and then exposed by high-speed scanning of the laser beam from the scanner unit 17. An electrostatic latent image based on predetermined image data is formed.

  Next, the electrostatic latent image formed on the surface of the photosensitive drum 23 when the positively charged toner carried on the developing roller 27 comes into contact with the photosensitive drum 23 by the rotation of the developing roller 27. That is, the surface of the photosensitive drum 23 that is uniformly positively charged is supplied to an exposed portion that is exposed to a laser beam and the potential of the photosensitive drum 23 is lowered, and is selectively carried to be visualized. By means of this, reversal development is achieved.

  The transfer roller 25 is disposed below the photosensitive drum 23 so as to face the photosensitive drum 23, and is rotatably supported by the drum cartridge 38. The transfer roller 25 is configured such that a metal roller shaft is covered with a roller made of a conductive rubber material, and a predetermined transfer bias is applied to the photosensitive drum 23 during transfer. . Therefore, the visible image carried on the surface of the photosensitive drum 23 is transferred to the sheet 3 while the sheet 3 passes between the photosensitive drum 23 and the transfer roller 25. The sheet 3 on which the visible image is transferred is conveyed to the fixing unit 19 via the conveyance belt 30.

  The fixing unit 19 is disposed on the downstream side of the process unit 18, and includes a heating roller 31, a pressing roller 32 that presses the heating roller 31, and a conveyance roller that is provided on the downstream side of the heating roller 31 and the pressing roller 32. 33 is provided.

  The heating roller 31 is made of a metal and has a halogen lamp for heating, and the toner transferred onto the paper 3 in the process unit 18 is passed while the paper 3 passes between the heating roller 31 and the pressing roller 32. Then, the sheet 3 is conveyed to a conveyance roller 34 and a paper discharge roller 35 provided in the main body casing 2 by a conveyance roller 33 of the fixing unit 19. Thereafter, the sheet 3 sent to the conveying roller 34 is discharged onto a discharge tray 36 by a discharge roller 35.

  In the laser printer 1, the residual toner remaining on the surface of the photosensitive drum 23 after being transferred to the sheet 3 by the transfer roller 25 is recovered by the developing roller 27, and the residual toner is recovered by a so-called cleanerless developing system. Yes. If the remaining toner is collected by such a cleaner-less developing method, a special member for removing the remaining toner such as a blade and a waste toner storage part are not required, and the apparatus configuration can be simplified.

  Further, the laser printer 1 includes a re-conveying unit 41 for forming images on both sides of the paper 3. In this re-conveying unit 41, a reversing mechanism portion 42 and a re-conveying tray 43 are integrally formed, and the reversing mechanism portion 42 is externally attached from the rear side of the main body casing 2, and the re-conveying tray 43 is In a state where it is inserted above the feeder unit 4, it is detachably mounted.

  The reversing mechanism portion 42 is externally attached to the rear wall of the main casing 2. The reversing mechanism portion 42 includes a reversing roller 46 and a re-conveying roller 47 in a substantially rectangular rectangular casing 44. Protruding.

  On the downstream side of the transport roller 33, the sheet 3 on which one side of the image is formed and transported by the transport roller 33 is directed to the transport roller 34 (solid line state) and to a reversing roller 46 described later. A flapper 45 is provided for selectively switching in the direction (virtual line state). The flapper 45 is rotatably supported at the rear part of the main casing 2 and is disposed in the vicinity of the downstream side of the conveying roller 33. An image is formed on one surface by excitation or non-excitation of a solenoid (not shown) and conveyed. The sheet 3 conveyed by the roller 33 is shaken so that it can be selectively switched between a direction toward the conveyance roller 34 (solid line state) and a direction toward the reversing roller 46 described later (virtual line state). It is provided to be movable.

  The reversing roller 46 is arranged on the downstream side of the flapper 45 and on the upper portion of the casing 44, and is composed of a pair of rollers so that the rotation can be switched between the forward direction and the reverse direction. The reversing roller 46 is configured to first rotate in the forward direction and transport the sheet 3 toward the reversing guide plate 48, and then rotate in the reverse direction to transport the sheet 3 in the reversing direction. .

  The re-conveying roller 47 is arranged on the downstream side of the reversing roller 46 and almost directly below the reversing roller 46 in the casing 44. The re-conveying roller 47 is composed of a pair of rollers. 43 so that it can be conveyed to 43.

  The reverse guide plate 48 is a plate-like member that extends further upward from the upper end of the casing 44, and is configured to guide the paper 3 fed by the reverse roller 46.

  When images are formed on both sides of the sheet 3, the reversing mechanism unit 42 first switches the flapper 45 in a direction in which the sheet 3 is directed to the reversing roller 46. A sheet 3 on which an image is formed is received. Thereafter, when the received sheet 3 is sent to the reversing roller 46, the reversing roller 46 rotates forward with the sheet 3 being sandwiched, and the sheet 3 is temporarily moved outside along the reversing guide plate 48. When the paper 3 is conveyed upward, most of the paper 3 is sent to the upper outer side, and the rear end of the paper 3 is sandwiched between the reversing rollers 46, the forward rotation is stopped. Next, the reverse roller 46 rotates in the reverse direction and conveys the paper 3 to the re-conveying roller 47 so as to be directed almost directly below in the reverse direction. The reverse rotation of the reversing roller 46 from the forward rotation is performed when a predetermined time elapses from when the paper passage sensor 56 provided on the downstream side of the fixing unit 19 detects the rear end of the paper 3. It is controlled. Further, when the conveyance of the sheet 3 to the reverse roller 46 is completed, the flapper 45 is switched to the original state, that is, the state in which the sheet 3 sent from the conveyance roller 33 is sent to the conveyance roller 34.

  Next, the sheet 3 conveyed in the reverse direction to the reconveying roller 47 is conveyed by the reconveying roller 47 to the reconveying tray 43 described below.

  The re-transport tray 43 includes a paper supply unit 49 to which the paper 3 is supplied, a tray main body 50, and a skew roller 51.

  The paper supply unit 49 is externally attached to the rear part of the main casing 2 below the reversing mechanism unit 42 and includes a curved paper guide member 52. In the sheet supply unit 49, the sheet 3 fed in the substantially vertical direction from the re-conveying roller 47 of the reversing mechanism unit 42 is guided in the substantially horizontal direction by the sheet guide member 52 and directed toward the tray body 50. Sending out in a substantially horizontal direction.

  The tray main body 50 has a substantially rectangular plate shape, and is provided in a substantially horizontal direction above the paper feed tray 6, and its upstream end is connected to the paper guide member 52 and its downstream end Is connected to the upstream end of the re-conveyance path 53 whose downstream end is connected to the middle of the paper feed conveyance path 65 in order to guide the sheet 3 from the tray body 50 to the second conveyance roller 10. ing.

  Further, in the middle of the conveyance direction of the sheet 3 of the tray main body 50, a skew roller 51 for conveying the sheet 3 while being in contact with a reference plate (not shown) is spaced at a predetermined interval in the conveyance direction of the sheet 3. Two are arranged.

  Each skew roller 51 is disposed in the vicinity of a reference plate (not shown) provided at one end in the width direction of the tray main body 50, and the skew drive roller 54 disposed in a direction substantially orthogonal to the conveyance direction of the paper 3. And the skew driving roller 54 across the sheet 3 and the axis thereof is arranged in a direction in which the feeding direction of the sheet 3 is inclined from the direction substantially perpendicular to the conveyance direction of the sheet 3 toward the reference plane. The skew follower roller 55 is provided.

Then, the sheet 3 sent out from the sheet supply unit 49 to the tray body 50 is again returned via the re-conveying path 53 while the one edge in the width direction of the sheet 3 is in contact with the reference plate by the skew roller 51. In the state where the front and back sides are reversed, the sheet is conveyed toward the image forming position. Then, the sheet 3 conveyed to the image forming position is in contact with the photosensitive drum 23 and the back surface of the sheet 3 is transferred to the image forming position. After the visible image is transferred, the sheet 3 is fixed by the fixing unit 19 and images are formed on both sides. The paper is discharged onto the paper discharge tray 36. {Development cartridge regeneration method}
The developing cartridge 24 attached to such a laser printer 1 has the used developing cartridge 24 as it is without being discarded after the toner in the filling chamber 26a is used for image formation. Reproduction is performed by refilling toner 24 and exchanging gears.

  Next, a method for regenerating such a developing cartridge 24 will be described.

  When the developing cartridge 24 is used before use, the suspension polymerization toner is filled in the filling chamber 26 a of the developing cartridge 24.

  When the developer cartridge 24 is used and such a suspension polymerization toner is used and a toner empty is displayed, the developer cartridge 24 is replaced by the user.

  Then, the used developing cartridge 24 removed from the laser printer 1 is temporarily collected, and first, the used developing cartridge 24 is more than the suspension polymerization toner used at the time of use before the developing cartridge 24. A toner having a low fluidity and a fluidity higher than that of a pulverized toner that has not been spheroidized is refilled.

  More specifically, in this method, instead of the suspension polymerization toner used at the previous use of the developing cartridge 24, it is contained in the suspension polymerization toner used at the previous use of the developing cartridge 24 at the time of refilling. Refilling the suspension polymerization toner containing the external additive in a smaller content than the external additive content, refilling the emulsion polymerization toner, or spheroidized pulverization Refill with toner.

By doing this, even if the side seal 58 is worn, the fluidity of the toner is low, so that it is possible to prevent the toner from leaking between the side seal 58 and both ends of the developing roller 27 in the axial direction. {Gear replacement method}
Next, the replacement of gears during the regeneration of the developing cartridge 24 will be described in detail with reference to FIGS. 4B, 5, 6, 7, 8A, and 8B. FIG. 4B is a right side view of the developing cartridge shown in FIG. FIG. 5 is a plan view of the gear mechanism portion in the A direction in FIG. FIG. 6 is a plan view of the gear mechanism portion in the B direction at the time of previous use. FIG. 7 is a B direction plan view of the gear mechanism portion after the gear change in the first embodiment. FIG. 8A is a B direction plan view of the developing roller driving gear in the previous use, and FIG. 8B is a B direction plan view of the developing roller driving gear after the gear change in the first embodiment.

  Here, as shown in FIG. 4, the direction in which the developer cartridge 24 is viewed from below is defined as the A direction, and the rotation axis direction of the developing roller is defined as the B direction as illustrated in FIG.

  As described above, the gear mechanism 59 in the previous use includes the developing roller driving gear 59a, the supply roller driving gear 59b, the input gear 59c, the intermediate gear 59d, and the agitator driving gear on the holder plate 61 supported by the side wall 56a. 59e is rotatably supported. Here, the developing roller drive gear 59a is fixed to the developing roller 27, the supply roller drive gear 59b is fixed to the supply roller 29, and the input gear 59c meshes with the development roller drive gear 59a and the supply roller drive gear 59b. Yes. The intermediate gear 59d is a two-stage gear composed of a large intermediate gear 59dn that meshes with the input gear 59c and a small intermediate gear 59dm that meshes with the agitator drive gear 59e. The agitator drive gear 59e is connected to the rotating shaft 40a of the agitator 40. When the developing cartridge 24 is mounted on the laser printer 1 and power is input from a motor (not shown) of the laser printer 1 to the input gear 59c via the coupling 80 of the input gear 59c, the input gear 59c is engaged. The developing roller 27 and the supply roller 29 are rotationally driven via the developing roller drive gear 59a and the supply roller drive gear 59b. Further, the agitator 40 is rotationally driven through an intermediate gear 59d that meshes with the input gear 59c and an agitator drive gear 59e that meshes with the intermediate gear 59d. Further, the gear supported by the gear mechanism 59 is made of a resin such as polyacetal, which is easy to regenerate, has a simple manufacturing process, and has a low manufacturing cost as compared with a reinforced resin containing glass fiber.

  By the way, as described above, when the developing cartridge 24 is regenerated by refilling the toner having lower fluidity, the torque applied to the gear included in the gear mechanism 59 in the subsequent use becomes larger than that in the previous use. There is a risk of gear tooth jumping.

  As the cause, the resistance from the toner to the agitator 40, the developing roller 27, the supply roller 29, and the like increases due to the low fluidity of the refilled toner.

  In particular, the increase in the torque applied to the developing roller drive gear 59a due to the reproduction of the developing cartridge 24 is particularly large as compared with other gears provided in the gear mechanism portion 59.

  The cause of this is that the toner passing between the developing roller 27 and the supply roller 29 after the reproduction has a large force against the rotation of the developing roller 27 and the supply roller 29, and the developing roller 27 and the layer thickness regulating blade. It can be mentioned that the toner that passes between 28 has a particularly large resistance to the rotation of the developing roller 27.

  Further, the rotary shaft that supports the gear included in the gear mechanism 59 and the bearing that rotatably holds the rotary shaft are worn as they are used. Then, due to wear, scrap scraps generated from the rotating shaft and the bearing are sandwiched between the bearing and the rotating shaft, and the resistance against rotation of the gear is increased. As wear further progresses, play occurs between the rotating shaft and the bearing, further increasing the resistance to gear rotation.

  Therefore, if the rotating shaft and the bearing are used as they are after the reproduction, the torque applied to the gear increases in the subsequent use, and the risk of gear tooth jumping is further increased.

  Therefore, in the first embodiment, as illustrated in FIGS. 6, 7, and 8, after refilling the toner, the developing roller driving gear 59 a is replaced with a developing roller driving gear 81 having a larger module. The input gear 59c has a module larger than the input gear 59c and meshes with the developing roller drive gear 81. The module is not changed from the input gear 59c, and the supply roller drive gear 59b and the intermediate gear 59d are connected. The input gear 82 is replaced with an input gear 82 which is a two-stage gear constituted by the meshing second input gear 82m.

  Here, both the developing roller drive gear 81 and the input gear 82 are easy to regenerate and have a simple manufacturing process, compared to a glass fiber-reinforced resin, etc., similar to the gear used during the previous use. It is made of a resin such as polyacetal that is low in production cost.

  8 (a) and 8 (b) are comparison diagrams of the developing roller driving gear 59a and the developing roller driving gear 81, respectively, and the size of the gear teeth 81x of the developing roller driving gear 81 is determined by the developing roller driving gear. It can be seen that the gear teeth 59ax of 59a are larger.

  As described above, when the module is replaced with a larger gear, the meshing between the gear teeth of the replaced gear becomes larger, and tooth skipping can be prevented. Further, since the thickness of the gear teeth in the rotation direction of the gears is increased, the strength of the gear teeth in the rotation direction is increased and tooth skipping can be prevented.

  Further, as described above, it is possible to exchange less gears by exchanging only the developing roller drive gear 59a that is expected to have the largest increase in torque applied after regeneration and the input gear 59c that meshes with it. Thus, gear tooth jumping can be prevented.

  Further, in the manufacture of a new developing cartridge 24 which is an unreproduced product, the environmental load is larger than that of a reinforced resin containing glass fiber, the manufacturing process is complicated, and there is no need to use a gear having a high manufacturing cost.

Further, since the developing roller drive gear 81 and the input gear 82 attached by exchanging gears are made of a material that can be easily regenerated, like the gear used before the exchanging, Compared to the case of using glass fiber reinforced resin, the environmental load can be suppressed. [Example 2]
A gear replacement method according to the second embodiment will be described with reference to FIGS. 5, 6, and 9.

  9A is a plan view of the developing roller drive gear 59a in the A direction during the previous use, and FIG. 9B is a plan view of the developing roller drive gear 83 in the A direction.

  Except as described below, the procedure is the same as that of the first embodiment.

  As shown in FIG. 9, the developing roller driving gear 59a is replaced with a developing roller driving gear 83 having a larger width in the rotation axis direction (B direction), that is, a tooth width.

  Similarly, the input gear 59c is replaced with an input gear having a larger width in the rotation axis direction (B direction), that is, a larger tooth width.

  FIGS. 9A and 9B are comparison diagrams of the thicknesses of the developing roller driving gear 59a and the developing roller driving gear 83 in the rotation axis direction (B direction), respectively. It can be seen that the thickness is larger than the thickness in the B direction of the developing roller drive gear 59a.

  As described above, since the thickness in the rotation axis direction (B direction) of the gear is increased, the strength in the rotation direction of the gear is increased and tooth jumping can be prevented.

  In addition, as described above, by replacing only the developing roller drive gear 59a, which is assumed to have the largest increase in torque applied after regeneration, and the input gear 59c that meshes with the developing roller drive gear 59a, fewer gears can be exchanged. Thus, gear tooth jumping can be prevented.

  Furthermore, the input gear attached by replacement is only thicker in the direction of the rotation axis (direction B) than the input gear 59c before replacement, and it is not necessary to use a two-stage gear. Accordingly, the manufacture of the input gear attached by replacement is not particularly difficult as compared with the manufacture of the input gear 59c attached before replacement.

  Further, in the manufacture of a new developing cartridge 24 which is an unreproduced product, the environmental load is larger than that of a reinforced resin containing glass fiber, the manufacturing process is complicated, and there is no need to use a gear having a high manufacturing cost.

Furthermore, the developing roller drive gear 83 and the input gear that are attached by exchanging the gear are made of a resin such as polyacetal, similar to the gear used before the replacement, and therefore, compared to a glass fiber-reinforced resin or the like. Reproduction is easy, the manufacturing process is simple, and the manufacturing cost is kept low. [Example 3]
A gear replacement method in the third embodiment will be described with reference to FIG.

  Except as described below, the procedure is the same as that of the first embodiment.

  In the third embodiment, the developing roller driving gear 59a and the input gear 59c shown in FIG. 10A are replaced with the developing roller driving gear 84 and the input gear 85, respectively, as shown in FIG. 10B. .

  Here, the input gear 85 is a two-stage gear composed of a first input gear 85m that meshes with the developing roller drive gear 84, and a second input gear 85n that meshes with the supply roller drive gear 59b and the intermediate gear 59d.

  The gear ratio of the developing roller driving gear 84 to the first input gear 85m before the gear replacement is larger than the gear ratio of the developing roller driving gear 59a to the input gear 59c in the previous use.

  When the gear is replaced, the peripheral speed of the developing roller driving gear 84 becomes smaller than the peripheral speed of the developing roller driving gear 59a before the replacement, that is, the torque applied to the developing roller driving gear 84 is before the replacement before the replacement. The torque applied to the developing roller driving gear 59a is smaller than that of the developing roller driving gear 59a.

  In addition, as described above, by replacing only the developing roller drive gear 59a, which is assumed to have the largest increase in torque applied after regeneration, and the input gear 59c that meshes with the developing roller drive gear 59a, fewer gears can be exchanged. Thus, gear tooth jumping can be prevented.

  Further, in the manufacture of a new developing cartridge 24 which is an unreproduced product, it is not necessary to use a gear having a high environmental load, a complicated manufacturing process, and a high manufacturing cost, such as a reinforced resin containing glass fiber.

Further, since the developing roller drive gear 84 and the input gear 85 that are attached by exchanging the gear are made of a material that can be easily regenerated, like the gear that was used before the exchanging, There is no increase in environmental impact. [Example 4]
Example 4 will be described with reference to FIG. FIG. 11 is an exploded view in the vicinity of the bearing of the developing roller.

  Except as described below, the procedure is the same as that of the first embodiment.

  The developing roller drive gear 59 a is fixed to a developing roller rotating shaft 91 that is a part of the developing roller 27 so as not to rotate with respect to the rotating shaft 91. The rotating shaft 91 is rotatably held by the bearing 90. The bearing 90 is fixed to the developing cartridge 24.

  The bearing 90 is worn by sliding with the rotating shaft 91 of the developing roller, and scraps are generated. As it is used, shavings accumulate between the bearing 90 and the developing roller rotating shaft 91, and as a result, the force resisting the rotation of the developing roller 24 increases. Further, as wear progresses, the rotation of the developing roller rotating shaft 91 is loosened, and the force resisting the rotation of the developing roller 24 further increases. As a result, the torque applied to the developing roller drive gear 59a gradually increases.

  In the fourth embodiment, after the toner refilling is completed, the bearing 90 is replaced with a new bearing as the gear is replaced.

In addition to the effects of the first embodiment, the bearing 90 is replaced with the refilling of the toner, so that the bearing is further worn after the developing cartridge 24 is regenerated, so that the torque applied to the developing roller driving gear 81 is increased. It can be prevented from increasing. [Example 5]
The fifth embodiment will be described with reference to FIG.

  FIG. 12 is an exploded view in the vicinity of the rotation shaft of the input gear.

  Except as described below, the procedure is the same as that of the first embodiment. During the previous use, the input gear 59c and the input rotary shaft 93 provided in the developing cartridge 24 are supported rotatably.

  The input rotary shaft 93 and the surface of the input gear 59c facing the peripheral surface of the input rotary shaft 93 are worn by sliding with each other. As the wear further progresses, the rotation of the input gear 59c becomes loose, and as a result, the torque applied to the input gear 59c increases.

  In the fifth embodiment, as illustrated in FIG. 12, after the refilling of the toner is completed, the gap between the input rotary shaft 93 and the surface of the input gear 82 that faces the peripheral surface of the input rotary shaft 93 is changed along with the gear replacement. A thin cylindrical sliding member 92 is sandwiched between the two.

  As the material of the sliding member 92, a resin having good sliding properties such as polyacetal is suitable.

  In addition to the effects of the first embodiment, as the toner is refilled, as described above, the thin cylindrical sliding member 92 is sandwiched between the input gear 59c and the input shaft, so that the input rotation is performed after the developing cartridge is regenerated. Further wear of the shaft 93 can prevent an increase in torque applied to the input gear 59c.

  Other embodiments will be described below.

  In the first embodiment, the gear is replaced with a larger module, but instead, a gear made of glass fiber reinforced resin or the like may be used.

  As a result, the strength in the rotational direction of the gear increases, and tooth jumping can be prevented.

  Further, in the manufacture of a new developing cartridge 24 which is an unreproduced product, the environmental load is larger than that of a reinforced resin containing glass fiber, the manufacturing process is complicated, and there is no need to use a gear having a high manufacturing cost.

  It is also possible to replace the gear alone.

  As shown in FIG. 5, the agitator drive gear 59e and the small intermediate gear 59dm are spur gears, but they may be replaced with helical gears.

  As a result, the thickness of the gear teeth in the rotation direction and the length of the tooth streaks are increased. As a result, the strength in the rotation direction of the gears is increased, and tooth jumping can be prevented. Furthermore, since the meshing rate, which is the number of gear teeth meshing at the same time, increases, the force applied to the gear teeth is dispersed, and tooth skipping can be prevented.

  Further, the helical gear may be replaced with a gear having a larger twist angle.

  As a result, the thickness of the gear teeth in the rotation direction and the length of the tooth streaks are increased. As a result, the strength in the rotation direction of the gears is increased, and tooth jumping can be prevented. Furthermore, since the meshing rate, which is the number of gear teeth meshing simultaneously, increases, the force applied to the gear teeth is dispersed, and tooth skipping can be prevented.

  In each of the embodiments described above, the gears to be exchanged are the developing roller drive gear 59a and the input gear 59c and the input gear. However, other gears may be targeted.

  For example, referring to FIGS. 5 and 6, the set of the agitator drive gear 59e and the intermediate gear 59d may be exchanged.

  Specifically, the agitator drive gear 59e is replaced with a larger agitator drive gear of the module. The intermediate gear 59d is composed of a small intermediate gear that is the same as the agitator drive gear after the replacement of the module and meshes with the agitator drive gear after the replacement, and a large intermediate gear that is not changed from the large intermediate gear 59dn before the replacement of the module. Replace with an intermediate gear.

  Thus, it is possible to prevent the agitator driving gear, in which the applied torque is increased, and the intermediate gear meshing with the agitator driving gear from being refilled with toner having lower fluidity.

  Further, all gears may be replaced with ones having a larger module.

  Moreover, you may attach the identification means which can be distinguished from the gear before replacement | exchange to the gear after replacement | exchange.

  Specific examples of the identification means include a mark and a color.

  In this way, the manufacturer can easily discriminate whether the product is recycled or not.

  Further, the used gear removed as the developing cartridge is recycled may be attached to another developing cartridge in which the gear can be used without being discarded.

  As a result, the used gear can be reused, so that the environmental load can be reduced and the manufacturing cost can be saved.

  The regeneration of the developing device in the present invention does not necessarily require a step of refilling the toner.

  In other words, just changing the gear is included in the reproduction of the developing device.

  Furthermore, it is included in the reproduction of the developing device even if a sliding member is sandwiched between the rotating shaft and the surface facing the rotating shaft peripheral surface of the gear.

  In each of the above embodiments, the developing cartridge as the developing device is not provided with the photosensitive drum, but the cartridge provided with the developing roller and the photosensitive drum is also included in the developing device of the present invention.

  Further, a developing device is a cartridge that is detachable from the image forming apparatus and includes at least a developing roller and a gear that transmits a driving force input from the image forming apparatus to the developing roller. In each of the above embodiments, a laser printer is used as the image forming apparatus. However, a facsimile or a multi-function machine using an electrophotographic process is also included in the image forming apparatus.

1 is a cross-sectional side view of a main part showing an embodiment of a laser printer as an image forming apparatus of the present invention. FIG. 2 is a side sectional view of a main part showing a developing cartridge of the laser printer shown in FIG. 1. FIG. 3 is a perspective view of a main part showing the vicinity of a side seal at an axial end portion of the developing roller in the developing cartridge shown in FIG. 2 (however, the developing roller is not mounted). 2A is a plan view, FIG. 2B is a right side view, and FIG. 2C is a left side view of the developing cartridge shown in FIG. It is an A direction top view of the gear mechanism part at the time of the previous use. It is a B direction top view of the gear mechanism part at the time of the previous use. It is a B direction top view of the gear mechanism part after the gear replacement in Example 1. FIG. (A) It is a B direction top view of the developing roller drive gear at the time of the previous use. (B) It is a B direction top view of the developing roller drive gear after gear replacement in Example 1. FIG. FIG. 6 is a comparative diagram comparing axial thicknesses of developing roller drive gears before use and after gear replacement in Example 2. (A) It is a B direction top view of the developing roller drive gear at the time of the previous use. (B) It is a B direction top view of the developing roller drive gear after the gear replacement in Example 3. It is an exploded view in the vicinity of the bearing of the developing roller. FIG. 6 is an exploded view of the input gear near the rotation shaft.

59 Gear mechanism 59a Developing roller drive gear 59b Supply roller drive gear 59c Input gear 59d Intermediate gear 59e Agitator drive gear

Claims (1)

A developer carrying member carrying the developer, a gear mechanism having a plurality of gears for transmitting the driving force input from the image forming apparatus main body to the developer carrying member, and slidable with respect to the gear; A regenerating method of a developing device comprising a rotating shaft that rotatably supports the gear, and detachable from the main body of the image forming apparatus,
A method of regenerating a developing device, comprising: a step of sandwiching a sliding member between the rotating shaft and a surface of the gear facing the peripheral surface of the rotating shaft.