JP5146135B2 - Drive device - Google Patents

Description

  The present invention relates to a copying machine, a printer, a facsimile machine, and a driving device that can be used in a multi-function machine.

  2. Description of the Related Art Conventionally, in a drive device mounted on this type of device, a disk-shaped or annular gear or pulley is rotatably disposed on a drive holder, and the power of a drive motor is transmitted by these rotating members. This driving device is mounted on, for example, an image forming apparatus, and rotationally drives a photosensitive drum, a toner supply roller, and the like, which are image carriers.

As a driving device mounted on the image forming apparatus, there is one in which an inertia member is disposed on the rotating shaft of the photosensitive drum in order to smoothly rotate the photosensitive drum and prevent a transfer shift and an exposure shift. Is provided.
Japanese Patent Laid-Open No. 5-19544

  However, the driving device of Patent Document 1 cannot obtain an effect unless an inertial body is attached to the rotating shaft. In other words, in a configuration in which a non-rotating fixed shaft is projected and a rotating member having an annular shape is mounted on the fixed shaft, an effect cannot be obtained even if an inertial body is provided. Therefore, an ideal configuration that can suppress vibration cannot be obtained in a drive device that transmits the driving force of the drive motor via a plurality of transmission gears.

  The present invention has been made in view of conventional problems, and an object of the present invention is to provide a drive device that can apply an inertial force to a predetermined rotating member regardless of the presence or absence of a rotating shaft.

In order to solve the above-mentioned problem, the drive device according to the first aspect of the present invention is the drive device in which the rotation member is rotatably attached to the resin drive holder, and the drive force of the drive means is transmitted by the rotation member and output. An inertia member is disposed on the holder so as to be positioned in parallel with the rotation member at a predetermined interval, and one of the rotation member and the inertia member is provided with a first magnet portion, and the other is provided with the first magnet portion. Is provided with a magnetic part that is attracted by the magnetic force of the second magnet part or the first magnet part having a reverse polarity, and when the rotating member is rotated, the inertia member is rotated substantially synchronously by the magnetic force . The inertia member is disposed with a partition wall of the drive holder with respect to the rotating member, and a support portion that rotatably supports the inertia member is provided .

  Specifically, it is preferable that a plurality of the first magnet portions are provided on the rotating member or the inertia member at a predetermined interval, and a plurality of second magnet portions or magnetic portions are provided on the inertia member or the rotating member at a predetermined interval. .

  According to this drive device, when the rotating member rotates with the driving force of the driving means, the magnetic part is attracted by the magnetic force of the first magnet part and the second magnet part, or by the magnetic force of the first magnet part, thereby inertia. The member follows and rotates. That is, the inertia member can be driven and rotated without being limited to whether or not the rotation member has a rotation shaft that integrally projects. Therefore, by adjusting the shape and material of the inertia member, a predetermined inertia force can be applied to the rotation member, and stable and smooth rotation can be realized. As a result, it is possible to prevent resonance, which is a factor that causes transfer deviation and exposure deviation.

In addition, the inertia member is disposed with the partition wall of the drive holder separated from the rotating member, and a support portion that rotatably supports the inertia member is provided, so that friction generated between the inertia member and the partition wall is reduced. In addition, an inertia member capable of inertial rotation can be realized.

In the drive device according to the first aspect of the present invention, it is preferable that the drive holder is provided with a storage portion that stores the inertia member in a closed state, and the support portion is provided in the storage portion.
In this case, the inertia member includes a disk portion positioned in parallel to the rotating member, and a shaft portion protruding from the center of the disk portion, and the support portion includes the shaft portion of the inertia member. It is preferable.

  Alternatively, the inertia member has an annular shape having a penetrating portion at a central portion, and a circular guide projection that penetrates through the penetrating portion is provided on a partition wall of the drive holder, and the support portion is provided as the guide projecting portion. It is preferable to provide the outer peripheral portion so as to form an annular shape.

The driving device of the second invention is a driving device in which a rotating member is rotatably attached to a resin-made driving holder, and the driving force of the driving means is transmitted by the rotating member and output. An inertia member is disposed so as to be positioned in parallel with the member at a predetermined interval, and a first magnet portion is provided on one of the rotating member and the inertia member, and a second electrode having a polarity opposite to that of the first magnet portion is provided on the other. A magnetic part that is attracted by the magnetic force of the two magnet parts or the first magnet part is provided, and when the rotating member is rotated, the inertia member rotates substantially synchronously by the magnetic force, and the partition of the drive holder A first guide protrusion protruding in the opposite direction with respect to the rotating member, and a second guide protrusion having an annular shape larger in diameter than the first guide protrusion, and the first and second guides. Protrusive It arranged a cover which closes the accommodation space, the inertia member has a configuration that consists of a number of granules that arranged in the housing space.
In this case, it is preferable that a magnet part capable of attracting the inertia member with a magnetic force is provided on at least a part of the first guide protrusion.

In the drive device according to the first and second inventions , a non-rotating fixed shaft projects from a partition wall of the drive holder, and the rotating member is rotatably attached to the fixed shaft.
In this case, it is preferable that the fixed shaft is a hollow shaft having a space portion extending in the axial direction, and the inertia member is provided with a shaft portion disposed in the space portion.

  In the driving device of the present invention, the rotation member is not limited to whether or not the rotation member has an integrally projecting rotation shaft. When the rotation member is rotated by the driving force of the driving means, the inertia member is driven by the magnetic force to rotate. To do. Then, by adjusting the shape and material of the inertia member, a predetermined inertia force can be applied to the rotation member, and stable and smooth rotation can be realized. As a result, it is possible to prevent resonance, which is a factor that causes transfer deviation and exposure deviation.

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

  FIG. 1 shows a tandem type color image forming apparatus to which a driving device 34 according to an embodiment of the present invention is applied.

  First, a schematic configuration of the image forming apparatus 10 will be described. The image forming apparatus 10 includes an intermediate transfer belt 12 in the approximate center inside the exterior body 11. The intermediate transfer belt 12 is supported on the outer periphery of the pair of rollers 13A and 13B and is driven to rotate counterclockwise in the drawing.

  Below the lower horizontal portion of the intermediate transfer belt 12, four image forming units 14Y, 14M, 14C, respectively corresponding to the respective colors of yellow (Y), magenta (M), cyan (C), and black (K). 14K are arranged side by side. Each of the image forming units 14Y, 14M, 14C, and 14K has a photosensitive drum 15Y, 15M, 15C, and 15K, respectively. Further, around each of the photosensitive drums 15Y, 15M, 15C, and 15K, charging devices 16Y, 16M, 16C, and 16K, exposure devices 17Y, 17M, 17C, and 17K, and a developing device are sequentially arranged along the rotation direction. 18Y, 18M, 18C, 18K, primary transfer rollers 19Y, 19M, 19C, 19K facing the respective photosensitive drums 15Y, 15M, 15C, 15K across the intermediate transfer belt 12, and cleaners 20Y, 20M, 20C, 20K. And are arranged respectively. Further, on the upper horizontal portion of the intermediate transfer belt 12, hoppers 21Y, 21M, 21C, and 21K that store toners of the respective colors are arranged.

  Further, a secondary transfer roller 22 is pressed against a portion of the intermediate transfer belt 12 supported by the roller 13B. A nip portion between the secondary transfer roller 22 and the intermediate transfer belt 12 is a secondary transfer that transfers the toner transferred from the photosensitive drums 15Y, 15M, 15C, and 15K to the intermediate transfer belt 12 onto the sheet S. Configure the area. Further, a belt cleaner 23 is pressed against a portion of the intermediate transfer belt 12 supported by the roller 13A. The belt cleaner 23 scrapes and collects toner remaining on the intermediate transfer belt 12 after the secondary transfer.

  A sheet feeding cassette 24 is detachably disposed at the lower portion of the image forming apparatus 10. The sheets S stacked and accommodated in the sheet feeding cassette are sent out one by one from the uppermost one by the rotation of the sheet feeding roller 25. The sheet S passes from the sheet feed cassette 24 through the nip portion of the pair of timing rollers 26 and 26, the nip portion of the secondary transfer roller 22, the fixing unit 27, and the sheet discharge rollers 28A and 28B. To be discharged. The fixing unit 27 is made of a conductive material, and is rotationally driven by a motor (not shown) and induction-heated by an exciting coil. The fixing unit 27 is pressed against the fixing roller 30 with a predetermined pressure by a swing device. And a pressure roller 31.

  In the image forming apparatus 10, the driving device 34 of the present invention is disposed on the outer side of the hoppers 21Y, 21M, 21C, and 21K, and uses the toner in the hoppers 21Y, 21M, 21C, and 21K mounted therein. The developing devices 18Y, 18M, 18C, and 18K are replenished. In addition, scrapers 32Y, 32M, 32C, and 32K are rotatably disposed inside the hoppers 21Y, 21M, 21C, and 21K, and end portions of the rotation shafts are exposed to the outside. And, on this rotating shaft, connecting gears 33Y, 33M, 33C, 33K are arranged.

  The drive device 34 includes a resin drive holder 35 disposed on the outer side of the four hoppers 21Y, 21M, 21C, and 21K. Inside the drive device 34, screws 32Y, 32M, 32C, and 32K, which are rotated members, are provided. Gears 52 to 56 for transmitting a driving force to the coupling gears 33Y, 33M, 33C, and 33K and outputting them are arranged.

  As shown in FIG. 3, the drive holder 35 has a box shape with an outer wall portion 36 closed at one end and an opening at the other end. A partition wall 37 is provided at the center in the longitudinal direction. Is divided into left and right gear arrangement portions 38A and 38B. And these gear arrangement | positioning parts 38A and 38B each arrange | position the five gearwheels 52-56.

  Specifically, the first gear mounting portion 39 is provided on the upper left side of each gear arrangement portion 38A, 38B. A non-rotating first fixed shaft 40 projects from the center of the first gear mounting portion 39. On the right side of the first gear mounting portion 39, there is a second gear mounting portion 41 that protrudes one step from the first gear mounting portion 39 to the opening end side so as to be positioned approximately at the center of the gear arrangement portions 38A and 38B. Is provided. A non-rotating second fixed shaft 42 projects from the center of the second gear mounting portion 41. On the right side of the second gear mounting portion 41, a third gear mounting portion 43 is provided that protrudes one step further from the second gear mounting portion 41 to the opening end side. A non-rotating third fixed shaft 44 projects from the third gear mounting portion 43. A fourth gear mounting portion 45 is provided on the lower left side of the second gear mounting portion 41. The fourth gear mounting portion 45 is recessed by one step from the second gear mounting portion to the bottom side. At the center of the fourth gear mounting portion 45, a fixed shaft mounting hole 46 for providing a fixed shaft (not shown) is provided. Further, a fifth gear mounting portion 47 is provided on the lower right side of the third gear mounting portion 43 so as to be located on the same plane as the third gear mounting portion 43. In the center of the fifth gear mounting portion 47, a fixed shaft mounting hole 48 similar to the fourth gear mounting portion 45 is provided.

  The drive holder 35 is provided with a gear insertion hole 49 so as to be positioned on the outer peripheral portion of the first gear mounting portion 39. As shown in FIG. 6, the drive gear 51 disposed on the output shaft of the drive motor 50 is disposed so as to be located in the gear disposition portions 38 </ b> A and 38 </ b> B from the gear insertion hole 49.

  In the drive holder 35, as shown in FIGS. 3 and 4, the first gear 52 is rotatably disposed on the first fixed shaft 40 of the first gear mounting portion 39. The first gear 52 includes a large-diameter first tooth portion 52a that meshes with the drive gear 51, and a small-diameter second tooth portion 52b protruding from the first tooth portion 52a. A second gear 53 is rotatably arranged on the second fixed shaft 42 of the second gear mounting portion 41. The second gear 53 includes a large-diameter first tooth portion 53a that meshes with the second tooth portion 52b of the first gear 52, and a small-diameter second tooth portion 53b that protrudes from the first tooth portion 53a. . A third gear 54 is rotatably disposed on the third fixed shaft 44 of the third gear attachment portion 43. The third gear 54 includes a tooth portion 54a that meshes with the second tooth portion 53b of the second gear 53, and a convex portion 54b that protrudes from the tooth portion 54a.

  And the 4th gearwheel 55 for connecting with the connection gearwheel 33Y of the screw 32Y of the hopper 21Y and outputting a driving force is rotatably arrange | positioned at the fixed shaft which the 4th gearwheel attachment part 45 does not illustrate. The fourth gear 55 includes a first tooth portion 55a that meshes with the second tooth portion 53b of the second gear 53, and a second tooth portion 53b of the second gear 53 that protrudes radially outward from the first tooth portion 55a. And a flange portion 55b positioned on the end face. Further, an annular recess 55c into which the drive gear 51 is fitted is provided on the end surface of the fourth gear 55, and a second tooth portion 55d that meshes with the coupling gear 33Y is provided on the outer peripheral surface of the recess 55c. It has been.

  Similarly, on the fixed shaft (not shown) of the fifth gear mounting portion 47, a fifth gear 56 for outputting a driving force by being connected to the connecting gear 33M of the screw 32M of the hopper 21M is rotatably arranged. . Similar to the fourth gear 55, the fifth gear 56 includes a first tooth portion 56a, a flange portion 56b, a concave portion 56c, and a second tooth portion 56d.

  When the drive device 34 configured as described above rotates when the drive motor 50 is energized, the rotational driving force is transmitted to the first gear 52 via the drive gear 51 to rotate the first gear 52. As a result, the fourth gear 55 is rotated via the second gear 53, and the screw 32Y of the hopper 21Y is rotated via the connecting gear 33Y. Further, the fifth gear 56 is rotated via the second gear 53 and the third gear 54, and the screw 32M of the hopper 21M is rotated via the connecting gear 33M. As a result, the toner in the hoppers 21Y and 21M is supplied to the developing devices 18Y and 18M through a passage (not shown).

  As shown in FIGS. 2 and 5, in the drive device 34 of the present embodiment, an inertia member 67 is provided in one gear arrangement portion 38 </ b> A, and the first gear serving as a rotating member is provided by the inertia member 67. An inertial force can be applied to 52. Needless to say, the inertia member 67 may be arranged in both the gear arrangement portions 38A and 38B.

  Specifically, the drive holder 35 is provided with an accommodating portion 57 for disposing the inertia member 67 so as to be located outside the first gear 52 with the outer wall portion 36 as a partition wall therebetween. Yes. The accommodating portion 57 includes a wall projecting outward so as to form an annular shape around the first fixed shaft 40, and an annular regulating rib 58 that regulates the inertia member 67 projects from the center thereof. Yes. Further, the first fixed shaft 40 is configured by a hollow shaft having a space portion 59 that extends along the axial direction and communicates with the accommodating portion 57. In other words, the first fixed shaft 40 is substantially uniform in thickness, and has a thin-walled shape that is substantially equal to the thickness of the outer wall portion 36 serving as a base portion. In addition, a first support portion 60 that protrudes inward so as to form a conical shape is provided inside the protruding end that is the bottom of the first fixed shaft 40 in order to rotatably support the inertia member 67. . Further, the open end of the accommodating portion 57 is closed by a separate cover 61. The cover 61 is provided with a second support portion 62 that protrudes in a conical shape at a position facing the first support portion 60.

  The first gear 52 is provided with an adsorption member disposing portion 63 that is recessed toward the second tooth portion 52b on the surface facing the outer wall portion. An adsorption member 64 having an annular shape is arranged in the adsorption member arrangement portion 63. As shown in FIG. 7A, the attracting member 64 includes first magnet portions 65 positioned at a predetermined interval. In the present embodiment, a pair of first magnet portions 65 and 65 are disposed so as to form a sector shape that is a quarter of a circle, and the opposing surfaces of the outer wall portion 36 have the same polarity (S pole). Has been. The first magnet portions 65 and 65 are integrated by a resin portion 66 that is a non-magnetic material.

  As shown in FIG. 2, the inertia member 67 is rotatably disposed in the accommodating portion 57 of the drive holder 35, and rotates substantially in synchronization with the first gear 52 when the first gear 52 is rotated. It is what I did. The inertia member 67 includes a disk part 68 positioned in parallel to the disk-shaped first gear 52 and a shaft part 70 protruding from the center of the disk part 68. As shown in FIG. 7B, the disk portion 68 is a pair of magnets that are attracted to the opposing positions of the first magnet portions 65 and 65 of the attracting member 64 by the magnetic force generated by the first magnet portions 65 and 65. Parts 69 and 69 are provided. These magnetic parts 69 and 69 are made of metal (iron) and are integrally provided by a resin that is a material for forming the inertia member 67. The shaft portion 70 protrudes from one surface of the disc portion 68 and is disposed in the space 59 of the first fixed shaft 40. The second shaft 70b protrudes from the other surface of the disc portion 68. It has. And the 1st support receiving part 71 supported rotatably by the 1st support part 60 is provided in the edge part of the 1st axis | shaft 70a. Similarly, the 2nd support receiving part 72 supported rotatably by the 2nd support part 62 is provided in the edge part of the 2nd axis | shaft 70b. And the full length of the 1st axis | shaft 70a is formed longer than the full length of the space part 59. FIG. Thereby, the disc part 68 is hold | maintained in a non-surface contact state with respect to the outer wall part 36 of the drive holder 35, and it is comprised enabling inertial rotation by reducing frictional resistance.

  In the drive device 34 configured as described above, the magnetic portions 69 and 69 of the inertia member 67 are attracted through the resin outer wall portion 36 by the magnetic force generated by the first magnet portion 65 of the first gear 52. As a result, the inertia member 67 is configured to be able to rotate freely when a rotational force is applied by the support of the support portions 60 and 62, but maintains a non-rotating state when the first gear 52 does not rotate.

  When the first gear 52 is rotated by the driving force of the drive motor 50, the magnetic member 69 is attracted by the magnetic force of the first magnet portion 65, and the inertia member 67 is driven and rotated. Note that this driven rotation action is provided by discontinuous first magnet portions 65 and 65 in the first gear 52 and discontinuous magnetic portions 69 and 69 in the inertia member 67 as well. This is because the structure is divided into a region and a non-adsorption region. Of course, even in this state, the inertia member 67 does not rotate when there is a resistance exceeding the adsorption force between the inertia member 67 and the drive holder 35, but in the present embodiment, the support portions 60 and 62 are not rotated. By providing the frictional force applied to the inertia member 67, the inertia member 67 can be reliably rotated following the rotation of the first gear 52.

  Thus, in the drive device 34 of this embodiment, the 1st gearwheel 52 which is a rotation member is a structure without the rotating shaft which protrudes integrally. Moreover, the inertia member 67 has a configuration in which the outer wall portion 36 that is a partition wall is provided with a space therebetween. However, regardless of these conditions, the inertia member 67 can be driven to rotate by the magnetic force with respect to the rotation of the first gear 52.

  Further, the driven rotation action by the magnetic force not only rotates the inertia member 67 by the first gear 52 but also applies a predetermined inertia force to the first gear 52 by the rotation of the inertia member 67 as in the prior art. In addition, stable and smooth rotation of the first gear 52 can be realized. Therefore, by adjusting the shape including the diameter of the inertia member 67 and the forming material, it is possible to prevent resonance, which is a factor that causes transfer deviation and exposure deviation.

  Specifically, the resonance region when the inertia member 67 is not applied is in a state indicated by a broken line in FIG. On the other hand, by arranging the inertia member 67 as in this embodiment, the resonance region can be moved as shown by the solid line in FIG. Therefore, by adjusting the diameter and weight of the disc portion 68 in the inertia member 67, it is possible to reliably prevent resonance, which is a cause of occurrence of transfer deviation and exposure deviation, in the most efficient operation state (environment). .

  FIG. 9 shows a driving device 34 according to the second embodiment. The driving device 34 of the second embodiment is different from the first embodiment in that the configuration of the support portions 60 and 62 is changed. Specifically, in the second embodiment, the first support portion 60 is configured by a concave portion that rotatably supports the tip outer peripheral portion of the first shaft 70a, and the second support portion 62 is formed on the second shaft 70b. It is comprised by the through-hole which supports a front-end | tip outer periphery part rotatably. In the second embodiment, the restriction rib 58 shown in the first embodiment is not provided. And even if it does in this way, the effect | action and effect similar to 1st Embodiment can be acquired.

  FIG. 10 shows a driving device 34 according to the third embodiment. The drive device 34 of the third embodiment is provided with a magnetic portion 69 of the inertia member 67 on the shaft portion 70 and a suction member 64 of the first gear 52 disposed at a position close to the shaft portion 70. This is different from the first embodiment. Specifically, as in the first embodiment, the first gear 52 of the third embodiment includes an adsorption member 64 in which first magnet portions 65 and resin portions 66 are alternately provided in the circumferential direction. The member 64 is disposed on the surface facing the second gear 53 and is disposed on the outer peripheral portion of the first fixed shaft 40. The inertia member 67 includes a disc portion 68 and a shaft portion 70 as in the first embodiment. The shaft portion 70 is provided with a notch portion at a predetermined interval in the circumferential direction so as to be located at the center portion of the attracting member 64, and a magnetic portion 69 is provided in the notch portion. And in 3rd Embodiment comprised in this way, the effect | action and effect similar to 1st Embodiment can be acquired.

  FIG. 11 shows a driving device 34 according to the fourth embodiment. The drive device 34 of the fourth embodiment is greatly different from the first embodiment in that the inertia member 67 is formed in an annular plate shape.

  Specifically, the inertia member 67 of the fourth embodiment has an annular shape like the suction member 64 of the first embodiment. The inertia member 67 is divided into four regions in the circumferential direction, and is provided so that the magnetic portions 69 and the resin portions are alternately positioned. In addition, it is preferable that the inner peripheral edge and the outer peripheral edge of the inertia member 67 are round portions having a substantially arc shape.

  In addition, an annular first guide projection 73 that restricts the inner peripheral portion of the inertia member 67 from the outer wall portion 36 protrudes from the housing portion 57 of the drive holder 35, and an annular shape is further provided on the outer peripheral portion. The 2nd guide protrusion 74 is protrudingly provided. Between the guide protrusions 73 and 74, a ring-shaped support portion 75 protrudes so as to form an annular shape so as to be positioned at the center of the surface of the inertia member 67. In order to reduce the frictional resistance with the inertia member 67, the protruding end of the ring-shaped support portion 75 is an arcuate rounded portion.

  The drive device 34 according to the fourth embodiment configured in this manner prevents the inertia member 67 from coming into surface contact with the drive holder 35 by the ring-shaped support portion 75, and thus rotates without resistance in the housing portion 57. Can be made. Therefore, similarly to the first embodiment, when the first gear 52 is rotated by the drive motor 50, the first gear 52 can be driven and rotated by an attracting action by magnetic force. As a result, the same operation and effect as in the first embodiment can be obtained.

  FIG. 12 shows a drive device 34 of the fifth embodiment. The drive device 34 of the fifth embodiment is greatly different from the respective embodiments in that the inertia member 67 is formed of a magnetic member having a grain (sphere) shape.

  Specifically, as in the fourth embodiment, the drive holder 35 of the fifth embodiment is provided with a first guide protrusion 73 and a second guide protrusion 74 inside the accommodating portion 57, and the opening of these tips is provided. Is closed by a cover 61. Also, the first gear 52 is provided with an adsorbing member 64 on the outer wall 36 side, as in the first embodiment. A large number of inertia members 67 having a spherical shape are disposed inside the accommodation space defined by the pair of guide protrusions 73 and 74. Further, the first guide projection 73 has a cylindrical magnet portion 76 that attracts the inertia member 67 with a magnetic force larger than the magnetic force of the first magnet portions 65 and 65 of the attracting member 64 acting through the outer wall portion 36. Is provided.

  The drive device 34 of the fifth embodiment configured as described above is in a state where a large number of spherical inertia members 67 are attracted to the magnet portion 76 of the drive holder 35 when the first gear 52 is not rotating. Eggplant. And when the 1st gearwheel 52 rotates, the circumference | surroundings of the magnet part 76 will be rotated with the magnetic force of the 1st magnet part 65. FIG. When the rotation of the first gear 52 and the rotation of the inertia member 67 are substantially synchronized and the rotation speed is increased, the inertia member 67 is separated from the magnet portion 76 by the centrifugal force, and the inner surface side of the second guide protrusion 74 Located in. Thereby, like the first embodiment, the inertia member 67 can be rotated by following the rotation of the first gear 52. As a result, the same operation and effect as in the first embodiment can be obtained. When driving by the drive motor 50 is stopped, the inertia member 67 is again attracted to the first guide protrusion 73 by the magnetic force of the magnet portion 76.

  In addition, the drive device 34 of this invention is not limited to the structure of the said embodiment, A various change is possible.

  For example, in each of the above embodiments, the first magnet portion 65 is disposed with the same polarity (S), but is disposed on the first gear 52 as shown in FIGS. 13 (A) and 13 (B). Of the pair of first magnet portions 65A and 65B of the attracting member 64, the polarity of one 65A may be the S pole and the polarity of the other 65B may be the N pole.

  In each of the above embodiments, the first magnet portion 65 is provided on the first gear 52 side that is the rotating member, and the magnetic portion 69 is provided on the inertia member 67 side. However, the magnetic portion is provided on the first gear 52 side. 69 may be provided, and the first magnet portion 65 may be provided on the inertia member 67 side.

  Further, in each embodiment, the first magnet portion 65 is provided in the first gear 52 that is a rotating member, and the magnetic portion 69 is provided in the inertia member 67. However, as shown in FIGS. 14 (A) and 14 (B). Moreover, you may provide the magnet parts 65 and 77 in both. In this case, when the first magnet portion 65 of the first gear 52 has the S polarity, the second magnet portion 77 provided on the inertia member 67 has the opposite N polarity.

  Furthermore, in each of the embodiments described above, the magnet portions 65 and 77 are configured to be positioned at a predetermined interval. However, as shown in FIGS. 15A and 15B, the first gear 52 has the same S polarity. A pair of first magnet portions 65A and 65A and a pair of first magnet portions 65B and 65B having opposite N polarities adjacent to each other, and the inertia member 67 similarly has a pair of second magnets having S polarity. The magnet portions 77A and 77A and the pair of second magnet portions 77B and 77B having N polarity may be provided alternately in the circumferential direction. When configured in this manner, the magnet portions 65A, 65B, 77A, and 77B having different polarities are attracted to each other and are kept facing each other. Thereby, it can mutually adsorb | suck with a strong magnetic force.

  In each of the embodiments described above, the first gear 52 that is directly rotated by the drive motor 50 is provided with the first magnet portion 65 and the inertia member 67 is arranged so as to be positioned in parallel at a predetermined interval. However, the inertia member may be arranged in the same manner for the fourth gear 55 rotated via the second gear 53. When the inertia members 67 and 67 for applying the inertia force to the first gear 52 and the fourth gear 55 are arranged as described above, the resonance region is divided into two as shown in FIG. In addition, individual vibration transmissibility can be lowered. Of course, it is good also as a structure which arrange | positions the inertia member 67 to each gear 52-56, respectively.

  In the embodiment, the screw 32Y, 32M, and the screw 32Y, 32M, for supplying toner from the hoppers 21Y, 21M, 21C, 21K in the image forming apparatus 10 by the driving device 34 of the present invention provided with the inertia member 67 driven to rotate by magnetic force. The configuration for rotationally driving the 32C and 32K has been described as an example, but the photosensitive drums 15Y, 15M, 15C, and 15K may be mounted as a driving device 34 for rotationally driving.

  That is, a toner image is formed on the photosensitive drum 15 based on the electrostatic latent image formed by exposure writing, the toner image is primarily transferred to a transfer belt, and the primary transferred toner image is transferred to a recording medium. In the image forming apparatus 10 that is secondarily transferred to (paper S), it is preferable that the driven member such as the photosensitive drum 15 and each roller is rotated by the driving device 34.

  Of course, the drive device 34 of the present invention is not limited to the image forming apparatus 10 and can be applied to any device as long as it has a rotated member that is driven to rotate, and can obtain the same operations and effects as described above. Can do.

1 is a schematic diagram illustrating an image forming apparatus to which a driving device according to an embodiment of the present invention is applied. It is sectional drawing which shows the principal part of the drive device of 1st Embodiment. It is a disassembled perspective view which shows the structure of the gearwheel which is a drive holder and a rotation member. It is a perspective view which shows the assembly | attachment state of FIG. It is a perspective view which shows the back side of a drive holder. It is a perspective view which shows the state which mounted | wore the drive holder with the cover. (A) is a top view which shows the adsorption | suction member arrange | positioned in a 1st gearwheel, (B) is a top view which shows an inertia member. It is a graph which shows the effect by the drive device of the present invention. It is sectional drawing which shows the principal part of the drive device of 2nd Embodiment. It is sectional drawing which shows the principal part of the drive device of 3rd Embodiment. It is sectional drawing which shows the principal part of the drive device of 4th Embodiment. It is sectional drawing which shows the principal part of the drive device of 5th Embodiment. (A), (B) is a top view which shows the modification of an adsorption | suction member and an inertia member. (A), (B) is a top view which shows the other modification of an adsorption | suction member and an inertia member. (A), (B) is a top view which shows the other modification of an adsorption | suction member and an inertia member. It is a graph which shows the effect at the time of arranging an inertia member in two gears.

Explanation of symbols

10. Image forming apparatus 32Y, 32M, 32C, 32K ... Screw (member to be rotated)
33Y, 33M, 33C, 33K ... coupling gear 34 ... drive device 35 ... drive holder 36 ... outer wall (partition)
50 ... Drive motor (drive means)
51 ... Drive gear 52 ... First gear (rotating member)
57 ... Accommodating part 59 ... Space part 60 ... First support part 61 ... Cover 62 ... Second support part 65, 65A, 65B ... First magnet part 66 ... Resin part 67 ... Inertial member 69 ... Magnetic part 70 ... Shaft part 71 ... 1st support receiving part 72 ... 2nd support receiving part 73 ... 1st guide protrusion 74 ... 2nd guide protrusion 75 ... Ring-shaped support part 76 ... Magnet part 77, 77A, 77B ... 2nd magnet part

Claims (9)

In the drive device that rotatably attaches the rotating member to the resin-made drive holder, and transmits the driving force of the driving means by the rotating member,
An inertia member is disposed on the drive holder so as to be parallel to the rotating member at a predetermined interval.
Among the rotating member and the inertia member, a first magnet part is provided on one side, and a second magnet part having a polarity opposite to the first magnet part or a magnetic part that is attracted by the magnetic force of the first magnet part is provided on the other side,
When the rotating member is rotated, the inertia member rotates substantially synchronously by adsorption by magnetic force ,
A drive device characterized in that the inertia member is disposed with a partition wall of the drive holder separated from the rotation member, and a support portion that rotatably supports the inertia member is provided .   The first magnet part is provided with a plurality of predetermined intervals on the rotating member or inertia member, and a plurality of second magnet parts or magnetic parts are provided on the inertia member or rotating member with predetermined intervals. The drive device according to 1. The drive device according to claim 1 , wherein the drive holder is provided with a storage portion that stores the inertia member in a closed state, and the support portion is provided in the storage portion. The inertia member includes a disk portion positioned in parallel to the rotating member and a shaft portion protruding from the center of the disk portion, and the support portion includes a shaft portion of the inertia member. The drive device according to claim 3 . The inertia member has an annular shape having a penetrating portion at the center,
The partition wall of the drive holder, provided with a circular guide projection penetrating said through portion, claim 3, characterized in that a said support portion so as to form an annular outer peripheral portion of said guide projection drive device according to. In the drive device that rotatably attaches the rotating member to the resin-made drive holder, and transmits the driving force of the driving means by the rotating member,
An inertia member is disposed on the drive holder so as to be parallel to the rotating member at a predetermined interval.
Among the rotating member and the inertia member, a first magnet part is provided on one side, and a second magnet part having a polarity opposite to the first magnet part or a magnetic part that is attracted by the magnetic force of the first magnet part is provided on the other side,
When the rotating member is rotated, the inertia member rotates substantially synchronously by adsorption by magnetic force ,
The partition wall of the drive holder is provided with a first guide protrusion that protrudes in the opposite direction with respect to the rotating member, and a second guide protrusion that has an annular shape larger in diameter than the first guide protrusion. A cover for closing the accommodation space between the first and second guide protrusions is disposed;
The drive device according to claim 1, wherein the inertia member is composed of a large number of granular bodies arranged in the accommodation space . The drive device according to claim 6 , wherein a magnet portion capable of attracting the inertia member with a magnetic force is provided on at least a part of the first guide protrusion. The partition wall of the drive holder, projecting the fixed shaft of the non-rotating, to any one of claims 1 to 7, characterized in that said rotating member in said fixed shaft rotatably mounted The drive device described. The fixed shaft is a hollow shaft having a space extending along the axial direction, the inertial body, according to claim 8, characterized in that a shaft portion that is disposed within the space Drive device.

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