JP5987400B2 - Conveying apparatus and image recording apparatus - Google Patents

Description

  The present invention relates to a conveyance device that conveys a sheet along a conveyance path, and an image recording apparatus that includes the conveyance device and that can record an image on a sheet conveyed along the conveyance path.

  A conveyance device that conveys a sheet along a conveyance path formed inside is known. As such a conveying apparatus, there is an image recording apparatus such as a printer or a multifunction machine. The transport device includes a plurality of rollers in the transport path. Each roller conveys a sheet by rotating. Some of such conveying devices and image recording devices are configured such that a roller different from the roller is stopped when a certain roller rotates normally. For example, Patent Document 1 discloses a paper feeding device that operates as described above.

  In the paper feeder described in Patent Document 1, the sun gear 9 rotates in the clockwise direction at the time of normal line feed, and the planetary gear 10 and the arm 11 are moved in the clockwise direction. Thereby, the planetary gear 10 and the connection gear 13 are connected. As a result, the friction roller and the paper discharge roller are interlocked. That is, both the friction roller and the paper discharge roller are rotated.

  On the other hand, in the paper feeding device described in Patent Document 1, at the time of reverse line feed, the sun gear 9 rotates counterclockwise, and the planetary gear 10 and the arm 11 are moved counterclockwise. As a result, the planetary gear 10 is separated from the connecting gear 13. As a result, the paper discharge roller is free with respect to the friction roller. That is, even if the friction roller rotates, the paper discharge roller does not rotate but remains stopped.

JP-A-6-227071

  Usually, in the paper feeder as described above, the sun gear 9, the planetary gear 10, and the connecting gear 13 are arranged so as to have a positional relationship that satisfies the following conditions. The above condition is that when the planetary gear 10 rotates, a force in a direction to engage with the connecting gear 13 acts on the planetary gear 10. Thereby, the rotational force of the sun gear 9 required for moving the planetary gear 10 to mesh with the connecting gear 13 can be reduced.

  However, when the sun gear 9, the planetary gear 10, and the connecting gear 13 are arranged so as to satisfy the positional relationship as described above, problems as described below arise. Since the force in the above direction acts on the planetary gear 10, the planetary gear 10 may not be separated from the connecting gear 13 even if the sun gear 9 rotates counterclockwise at the time of reverse line feed. In this state, when the connecting gear 13 rotates for some reason, the planetary gear 10 rotates, and the meshing between the connecting gear 13 and the planetary gear 10 is maintained accordingly. If reverse line feed is continued in a state where the meshing between the connecting gear 13 and the planetary gear 10 is maintained, the skipping of the coupling gear 13 and the planetary gear 10 will eventually occur. This tooth skip is accompanied by noise.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to appropriately release the meshing state of the planetary gear in a transport device including a planetary gear that switches the presence or absence of drive transmission by moving. Is to provide a structure.

  (1) The conveyance device according to the present invention rotates in the first rotation direction when the drive source rotates forward and backward, and the drive source rotates forward, and conveys the sheet in the conveyance path along the conveyance direction. And a first roller that rotates in a second rotation direction opposite to the first rotation direction by reversing the drive source, and is provided downstream of the first roller in the conveyance direction. The second roller for conveying the sheet and the first rotational driving force of the first roller in the first rotational direction are transmitted to the second roller, and the second rotational driving force in the second rotational direction is transmitted to the second roller. A first drive transmission unit that is not transmitted to the second roller; and the second rotational driving force of the first roller is transmitted to the second roller, and the first rotational driving force of the first roller is transmitted to the second roller. A second drive transmission unit that is not transmitted. The second drive transmission unit includes at least one first gear, and includes a first transmission unit that transmits the first rotational driving force from the first roller, and at least one second gear. A second transmission unit that transmits the second rotational driving force from the first roller to the second roller, and a rotational driving force from the first roller that is transmitted to the first transmission unit is applied to rotate. A sun gear, an arm that rotates coaxially with the sun gear, and a planetary gear that is rotatably supported by the arm and revolves in the direction of rotation of the sun gear while meshing with the sun gear. . When the second rotational driving force is transmitted from the first transmission unit, the sun gear rotates in a third rotation direction in which the planetary gear meshes with the second gear, and the sun transmission unit performs the first rotation from the first transmission unit. When one rotation driving force is transmitted, the planetary gear rotates in a fourth rotation direction away from the second gear. The center of rotation of the sun gear is the tooth surface of the planetary gear when the second gear driven and transmitted via the first drive transmission unit rotates with the planetary gear and the second gear engaged. And a common normal line to the tooth surface of the second gear, it is located on the opposite side of the rotation center of the planetary gear.

  When the sun gear, the planetary gear, and the second gear are arranged in the positional relationship as in the present configuration, the force in the direction to mesh with the second gear does not act on the planetary gear. Therefore, when the sun gear rotates in the fourth rotation direction with the planetary gear and the second gear engaged, the planetary gear is easily separated from the second gear. Therefore, according to this configuration, the planetary gear should be separated from the second gear, that is, the second gear should be rotated by the driving force transmitted through the first drive transmission unit, and the second drive transmission unit. In a state where the driving force should not be transmitted via the second gear, the second gear can be prevented from erroneously rotating due to the driving force transmitted via the second drive transmitting portion. .

  (2) In a state where the planetary gear and the second gear are engaged with each other, the tops of the teeth of the planetary gear are located outside the reference circle of the second gear in the radial direction of the second gear.

  Thereby, the planetary gear can be easily separated from the second gear.

  (3) Between the teeth of the second gear and between the top of each tooth and the reference circle, the top of the teeth of the planetary gear meshed with the second gear is A restraining member that restrains entry into the radially inner side is formed.

  For example, when at least one of the one that supports the shaft that is the rotation center of the second gear or the one that supports the shaft that is the rotation center of the sun gear is deformed, the rotation center of the second gear and the rotation center of the sun gear are changed. It may approach. However, since the stop member is formed, the contact position between the planetary gear and the second gear is outside the reference circle of the second gear in the radial direction. Therefore, according to this configuration, even when the rotation center of the second gear and the rotation center of the sun gear approach each other, the planetary gear can be easily separated from the second gear.

  (4) The transport device of the present invention is provided in the abutting portion and the arm, and abuts on the abutting portion in a state where the planetary gear meshes with the second gear, and the planetary gear is in contact with the second gear. And a contacted portion that is separated from the contact portion in a state of being separated from the contact portion.

  According to this configuration, the contact position of the planetary gear with respect to the second gear is reliably maintained by the contact portion and the contacted portion contacting each other. Therefore, the planetary gear can be easily separated from the second gear.

  (5) The first drive transmission unit is provided coaxially with the first pulley that rotates in conjunction with the rotation of the first roller and the second roller, and when the first rotational driving force is transmitted, When the second rotational driving force is transmitted in conjunction with the second roller, the one-way clutch that idles with respect to the second roller, the second pulley having the one-way clutch, and the first pulley And a belt that spans the second pulley and is capable of circumferential movement between the first pulley and the second pulley.

  In this configuration, the first drive transmission unit transmits the first rotational driving force from the first roller to the second roller via the belt, while the second rotational driving force is transmitted to the second roller due to the presence of the one-way clutch. Do not transmit. As described above, this configuration is a preferable configuration for realizing the function of the first drive transmission unit (1).

  (6) The transport device of the present invention further includes a friction resistance member that imparts a friction resistance force against the rotation of the planetary gear to the planetary gear.

  When the sun gear rotates in the third rotation direction by rotating the first roller in the second rotation direction, the planetary gear revolves in the third rotation direction and meshes with the second gear. Thereafter, the planetary gear rotates in conjunction with the rotation of the sun gear. Thereby, the second gear rotates. However, when the sun gear, the planetary gear, and the second gear are arranged in the positional relationship as described in (1) above, when the planetary gear rotates as described above, the planetary gear includes the second gear. The force acts in the direction away from the head. If the planetary gear is separated from the second gear by the action of the force, the second gear to be rotated cannot rotate when the first roller rotates in the second rotation direction.

  Therefore, the transport device of this configuration includes a frictional resistance member. As a result, the planetary gear is subjected to a force in the direction from the planetary gear to the second gear, that is, a force to be separated from the second gear, by a frictional resistance force generated during rotation. Then, when the force in the direction from the planetary gear to the second gear is larger than the force in the direction from the second gear to the planetary gear, the planetary gear can be prevented from being erroneously separated from the second gear.

  (7) The conveyance device of the present invention is provided between the conveyance device according to any one of (1) and (2) above and the first roller and the second roller in the conveyance direction, Reciprocating in the main scanning direction orthogonal to the transport direction, and moving in the main scanning direction by contacting the recording unit for recording an image on the sheet and the recording unit moving in the main scanning direction And a switching unit that switches whether or not to transmit the rotational driving force to the second drive transmission unit.

  In the present invention, the planetary gear is easily separated from the second gear. Therefore, in the present invention, the meshing state of the planetary gear can be appropriately released in the transport device including the planetary gear that switches the presence or absence of drive transmission by moving.

FIG. 1 is a perspective view of the multifunction machine 10. FIG. 2 is a longitudinal sectional view schematically showing the internal structure of the printer unit 11. FIG. 3 is a perspective view of the drive transmission mechanism 50 and the transport rollers 60, 62, 45. FIG. 4 is a perspective view of the drive transmission mechanism 50 and the transport rollers 60, 62, 45. FIG. 5 is a plan view of the drive transmission mechanism 50 and the transport rollers 60, 62, 45. FIG. 6 is a schematic diagram showing the transmission relationship between the roller, belt, gear, and pulley of the drive transmission mechanism 50. FIG. 7A is a plan view schematically showing meshing of the respective gears 51, 75, 78, 88 when the switching gear 51 is at the first drive transmission position, and FIG. FIG. 6 is a plan view schematically showing meshing of the respective gears 51, 75, 78, 88 when is a second drive transmission position. FIG. 8 is a table for explaining the transport direction of the recording paper 12 by the feeding roller 25 and the transport rollers 60, 62, 45, 68 with respect to the position of the switching gear 51. FIG. 9 is a side view schematically showing the positional relationship among the sun gear 97, the planetary gear 98, and the second gear 101. FIG. 10 is a side view schematically showing a meshing portion between the planetary gear 98 and the second gear 101. FIG. 11 is a longitudinal sectional view schematically showing the internal structure of the printer unit 11 with the third transport roller 45 and the spur 46 removed from FIG. FIG. 12 is a side view schematically showing an arrangement relationship among the sun gear 97, the planetary gear 98, and the second gear 101 in the first modification. FIG. 13 is a side view schematically showing the sun gear 97, the planetary gear 98, the second gear 101, and the arm 102 in Modification 2. FIG. 13A shows a contacted portion 143, a contact portion 144, and the like. A state in which the contacted part 143 and the contacted part 144 are separated from each other is shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. The embodiment described below is merely an example of the present invention, and it is needless to say that the embodiment of the present invention can be changed as appropriate without departing from the gist of the present invention. The multifunction machine 10 is installed and used in the state shown in FIG. In the present embodiment, three directions indicated by arrows in FIG. 1 are a vertical direction 7, a front-rear direction 8, and a left-right direction 9. Further, in the following description, the vertical direction 7 is defined with reference to a state in which the multifunction machine 10 is installed so as to be usable (the state in FIG. 1), and the side in which the opening 13 is formed is the front side (front side). 8 is defined, and the left-right direction 9 is defined when the multifunction machine 10 is viewed from the front side. Note that the three directions shown in FIG. 1 are displayed in the same manner in the other drawings. Furthermore, in the following description, “orientation” means a state of facing from one point to the other distant point, and “direction” is a state of facing between two distant points. That is, the “direction” includes a state in which the point is directed from one point to the other point and the state in which the other point is directed to the one point.

[Overall structure of MFP 10]
As shown in FIG. 1, the multifunction machine 10 (an example of the image recording apparatus of the present invention) includes a printer unit 11 at the bottom. The multifunction machine 10 has various functions such as a facsimile function and a print function. In the present embodiment, the multifunction machine 10 has a double-sided image recording function for recording images on both sides of the recording paper 12 (an example of the sheet of the present invention, see FIG. 2) as a printing function. You may have only a function. The printer unit 11 has an opening 13 formed in the front. A feed tray 20 (see FIG. 2) and a discharge tray 21 (see FIG. 2) on which the recording paper 12 can be placed can be inserted and removed in the front-rear direction 8 from the opening 13. Note that image recording by the multifunction device 10 is not limited to the recording paper 12, but the multifunction device 10 may record an image on a label surface of a CD or DVD, for example. In this case, the CD or DVD is placed on a thin plate-shaped media tray and inserted into the multifunction machine 10 through the opening 13 or the like.

  As shown in FIG. 2, a feeding roller 25 is provided on the upper side of the feeding tray 20. The feeding roller 25 can abut on the recording paper 12 placed on the feeding tray 20 and the side facing the placement portion on which the recording paper 12 is placed. The feeding roller 25 is rotated in the second rotational direction by applying a reverse driving force from a conveying motor 71 (an example of the driving source of the present invention, see FIGS. 3 to 5). Thereby, the recording paper 12 placed on the feeding tray 20 is fed to the first conveyance roller 60 through the first conveyance path 65 (an example of the conveyance path of the present invention). When the feeding roller 25 is rotated in the second rotation direction, the recording paper 12 is conveyed in the first direction 15. The drive transmission from the first conveying roller 60 and the conveying motor 71 to the feeding roller 25 will be described later.

  A first transport path 65 extends from the rear end of the feed tray 20. The first transport path 65 includes a curved portion and a straight portion. The first transport path 65 is partitioned by an outer guide member 18 and an inner guide member 19 that face each other with a predetermined interval. The recording paper 12 accommodated in the feeding tray 20 is conveyed so as to make a U-turn from the lower side to the upper side of the curved portion, and then conveyed along the straight portion and conveyed to the recording unit 24. The recording paper 12 on which image recording has been performed by the recording unit 24 is conveyed through the linear portion and discharged to the discharge tray 21. That is, the recording paper 12 is conveyed in the first direction 15 (an example of the conveying direction of the present invention) indicated by a one-dot chain line arrow in FIG. The recording unit 24 will be described later.

  In addition, the multifunction machine 10 includes a transport device inside. Each of the transport devices includes the following, which will be described later. That is, the transport device includes a transport motor 71 (see FIGS. 3 and 4), a first transport roller 60, a second transport roller 62, a first drive transmission unit 26 (see FIGS. 3 to 5), and a second drive transmission. A portion 27 (see FIGS. 3 to 5) and a leaf spring 135 (see FIGS. 3 and 4) are provided.

[First Conveying Roller 60, Second Conveying Roller 62, and Third Conveying Roller 45]
As shown in FIG. 2, the first conveyance path 65 includes a first conveyance roller 60 (an example of the first roller of the present invention) and a pinch roller 61 on the upstream side in the first direction 15 from the recording unit 24. A roller pair is provided, and a roller pair including a second transport roller 62 and a spur 63 is provided downstream of the recording unit 24 in the first direction 15, and is provided downstream of the second transport roller 62 in the first direction 15. A roller pair including a third transport roller 45 (an example of the second roller of the present invention) and a spur 46 is provided. Each roller pair conveys the recording paper 12 by rotating with the recording paper 12 sandwiched therebetween.

  The first transport roller 60 is rotated by a driving force applied from the transport motor 71. The conveyance motor 71 is driven forward and backward. The first conveyance roller 60 to which the driving force is applied from the conveyance motor 71 that is normally driven to rotate rotates in the first rotation direction. Here, the first rotation direction is a rotation direction in which the recording paper 12 is conveyed in the first direction 15. The first conveyance roller 60 to which the driving force is applied from the conveyance motor 71 that is driven in the reverse direction rotates in the second rotation direction opposite to the first rotation direction. Here, the second rotation direction is a rotation direction in which the recording paper 12 is conveyed in a direction opposite to the first direction 15. The first conveying roller 60 transmits the driving force to the second conveying roller 62 and the third conveying roller via a drive transmission mechanism 50 (see FIGS. 3 to 6) described later.

  In the present embodiment, the first conveyance roller 60 abuts on the recording surface of the sheet conveyed through the first conveyance path 65 (that is, the surface on which an image is recorded by the recording unit 24 described later), and the second conveyance roller 60 The roller 62 and the third conveyance roller 45 abut from the back side of the recording surface of the sheet. That is, when the first transport roller 60 rotates in the first rotation direction and transports the recording paper 12 in the first direction 15, the second transport roller 62 and the third transport roller 45 rotate in the second rotation direction. On the other hand, when the 1st conveyance roller 60 rotates in the 2nd rotation direction, the 2nd conveyance roller 62 and the 3rd conveyance roller 45 rotate in the 1st rotation direction.

  A first position 36 exists between the second conveyance roller 62 and the third conveyance roller 45 in the first conveyance path 65. During double-sided image recording, the recording paper 12 conveyed through the first conveyance path 65 is switched back downstream of the first position 36 and conveyed toward a second conveyance path 67 described later.

[Recording unit 24]
As shown in FIG. 2, the recording unit 24 is provided on the downstream side in the first direction 15 of the first transport roller 60 and on the upstream side in the first direction 15 of the second transport roller 62. A platen 42 is provided below the recording unit 24 and at a position facing the recording unit 24. The platen 42 supports the recording paper 12 conveyed through the first conveyance path 65. The recording unit 24 records an image on the recording paper 12 supported by the platen 42 by a known inkjet method. The recording unit 24 includes a recording head 38 on which a plurality of nozzles that eject ink droplets are formed on the recording paper 12, and a carriage 40 on which the recording head 38 is mounted.

  The carriage 40 is supported by the frame of the printer unit 11 so as to be capable of reciprocating in the left-right direction 9 (an example of the main scanning direction of the present invention) orthogonal to the front-rear direction 8. The carriage 40 is connected to a carriage driving motor (not shown) via a known belt mechanism. The carriage 40 is reciprocated in the left-right direction 9 by the driving force transmitted from the carriage driving motor. With the recording paper 12 supported on the platen 42, the carriage 40 is reciprocated. When the carriage 40 is reciprocated, ink droplets are ejected from the recording head 38. As a result, an image is recorded on the recording paper 12 supported by the platen 42. The recording unit 24 may record an image on the recording paper 12 by, for example, an electrophotographic method other than the ink jet method.

[Path switching member 41 and second transport path 67]
As shown in FIG. 2, the path switching member 41 is provided between the second transport roller 62 and the third transport roller 45 in the first transport path 65, that is, at the first position 36. The path switching member 41 includes auxiliary rollers 47 and 48, a flap 49, and a shaft 87. The flap 49 extends substantially in the first direction 15 from the shaft 87 and is pivotally supported by the shaft 87 so as to be rotatable. Spur-shaped auxiliary rollers 47 and 48 are pivotally supported on the flap 49.

  The flap 49 has a discharge attitude (position indicated by a broken line in FIG. 2) located above the first position 36 relative to the inner guide member 19 and an inverted attitude in which the extended end portion 49 </ b> A is located below the first position 36. (The posture shown by the solid line in FIG. 2).

  The flap 49 is in a reverse posture due to its own weight in a normal state, but when the flap 49 is lifted by the recording paper 12 conveyed through the first conveyance path 65, the flap 49 rotates to a discharge posture. Thereafter, the flaps 49 (specifically, the auxiliary rollers 47 and 48) contact the recording paper 12 and guide the recording paper 12. When the upstream end of the recording paper 12 in the first direction 15 passes through the auxiliary roller 47, the flap 49 rotates from the discharge posture to the reverse posture by its own weight. As a result, the upstream end of the recording paper 12 in the first direction 15 moves downward. As a result, the upstream end of the recording paper 12 in the first direction 15 faces the second transport path 67 described later. In this state, when the rotation of the third conveyance roller 45 in the second rotation direction is continued, the recording paper 12 is conveyed in the first direction 15 and discharged to the discharge tray 21. On the other hand, when the rotation direction of the third conveyance roller 45 is switched to the first rotation direction, the recording paper 12 is conveyed in the direction opposite to the first direction 15 and guided to the second conveyance path 67.

  The second conveyance path 67 is branched from the first conveyance path 65 at the first position 36 so as to merge with the first conveyance path 65 at the second position 37 upstream of the first conveyance roller 65 in the first direction 15. This is a route extending to That is, the second transport path 67 is connected to the first transport path 65 at the first position 36 and the second position 37. The second transport path 67 is partitioned by the guide members 31 and 32.

[Fourth transport roller 68]
As shown in FIG. 2, the fourth conveyance roller 68 and the driven roller 69 are provided in the second conveyance path 67. The fourth conveyance roller 68 is disposed in the second conveyance path 67 at a position below and opposite to the driven roller 69.

  A driving force is applied to the fourth transport roller 68 from the transport motor 71 via a third drive transmission unit 28 of the drive transmission mechanism 50 described later. Then, the fourth conveyance roller 68 rotates in the direction in which the recording paper 12 is conveyed in the second direction 16 along the second conveyance path 67. Specifically, the fourth transport roller 68 rotates only in the first rotation direction. Here, the second direction 16 is a direction from the first position 36 toward the second position 37 along the second conveyance path 67. The second direction 16 is a direction indicated by a two-dot chain line arrow in FIG.

  As described above, when the recording sheet 12 conveyed to the second conveying path 67 by the third conveying roller 45 is sandwiched between the fourth conveying roller 68 and the driven roller 69, the recording sheet 12 is moved to the fourth conveying roller. 68 in the second direction 16. As a result, the recording paper 12 is conveyed upstream in the first direction 15 relative to the first conveying roller 60. The drive transmission from the conveyance motor 71 to the fourth conveyance roller 68 will be described later.

[Drive transmission mechanism 50]
As shown in FIGS. 3 to 5, the printer unit 11 is provided with a drive transmission mechanism 50. The drive transmission mechanism 50 includes a roller pulley 76, a motor pulley 58, a first belt 77, a first drive transmission unit 26, a second drive transmission unit 27, a third drive transmission unit 33, a fourth drive transmission unit 28, and a feed drive transmission unit. 29 and a switching unit 30. In the present embodiment, the second drive transmission unit 27 and the third drive transmission unit 33 are examples of the second drive transmission unit of the present invention.

  As shown in FIG. 8, the drive transmission mechanism 50 rotates the rollers 60, 62, 45, 68, and 25 so that the recording paper 12 is conveyed in the direction shown in FIG. 8. That is, the rollers 60, 62, 45, 68, and 25 are rotated according to the position of the switching gear 51 of the switching unit 30 and the normal rotation and reverse rotation of the conveyance motor 71. Each of the rollers 60, 62, 45, 68, 25 is one of the first drive transmission unit 26, the second drive transmission unit 27, the third drive transmission unit 33, the fourth drive transmission unit 28, or the feeding drive transmission unit 29. Driven by the transfer motor 71 via the rotator, it rotates. In FIG. 8, each of the rollers 60, 62, 45, 68, and 25 is driven to transmit the rotational driving force of the conveying motor 71 by a drive transmitting portion indicated in parentheses.

  As shown in FIG. 5, the roller pulley 76 is attached to the shaft 34 of the first transport roller 60 on the left side of the first transport path 65. As shown in FIGS. 3 to 5, a motor pulley 58 is attached to the rotation shaft of the conveyance motor 71 in the conveyance motor 71. An endless annular first belt 77 is stretched between the roller pulley 76 and the motor pulley 58. Thereby, the rotational driving force of the conveyance motor 71 is transmitted to the first conveyance roller 60. Specifically, when the conveyance motor 71 is rotated forward, the first conveyance roller 60 rotates in the first rotation direction, and when the conveyance motor 71 is reversed, the first conveyance roller 60 is rotated in the second rotation direction. Rotate to.

[First drive transmission unit 26]
As shown in FIGS. 3 to 6, the first drive transmission unit 26 includes a left gear 52, a lower gear 80, a first pulley 81, a second pulley 82, and a second belt 83 (an example of the belt of the present invention). It has. The left gear 52 is provided on the left side of the conveyance path 65 on the shaft 34 of the first conveyance roller 60. The lower gear 80 is provided below the left gear 52 and meshes with the left gear 52. The first pulley 81 is attached to the right side of the lower gear 80 and rotates coaxially and integrally with the lower gear 80. As a result, the first pulley 81 rotates in conjunction with the rotation of the first transport roller 60. The second pulley 82 is attached to the shaft 64 of the second transport roller 62. An endless annular second belt 83 is bridged between the first pulley 81 and the second pulley 82. As a result, when the first transport roller 60 rotates, the second belt 83 makes a circumferential motion. As a result, the rotational driving force of the first transport roller 60 is transmitted to the second transport roller 62.

[Third drive transmission unit 33]
As shown in FIGS. 3 to 6, the third drive transmission unit 33 includes a third pulley 83, a fourth pulley 85, and a third belt 86. The third pulley 83 is attached to the left side of the second pulley 82 on the shaft 64 and rotates coaxially and integrally with the second pulley 82. The fourth pulley 85 is attached to the shaft 44 of the third transport roller 45. An endless annular third belt 86 is bridged between the third pulley 84 and the fourth pulley 85. Thereby, the rotational driving force of the second transport roller 62 is transmitted to the third transport roller 45. That is, the third transport roller 45 is driven by the rotational driving force transmitted from the second transport roller 62.

  In the following description, the clockwise direction (that is, the second rotational direction) and the counterclockwise direction (that is, the first rotational direction) are the rotational directions of the rollers and the gears in FIG. That is, the rotation direction of each roller and each gear when each roller and each gear is viewed from the left side. Therefore, for example, when each roller and each gear is viewed from the right side, it goes without saying that the clockwise direction is the first rotation direction and the counterclockwise direction is the second rotation direction. A known one-way clutch (specifically, a needle clutch) is provided inside the second pulley 82. That is, the second pulley 82 is attached to the shaft 64 via the one-way clutch. Accordingly, as shown in FIG. 6, in this embodiment, the shaft 64 is rotated clockwise (that is, in the second rotation direction) when the transport motor 71 rotates in the forward direction. It is not rotated when reversing. As a result, when the conveying motor 71 rotates in the forward direction, the forward rotation driving force is transmitted to the conveying rollers 60, 62, 45, and the conveying rollers 60, 62, 45 convey the recording paper 12 in the first direction 15. Rotate as you do. Specifically, in the present embodiment, the first conveyance roller 60 is rotated counterclockwise (that is, in the first rotation direction), and the second conveyance roller 62 and the third conveyance roller 45 are rotated in the clockwise direction (that is, in the second rotation direction). To be rotated. On the other hand, when the conveyance motor 71 rotates in the reverse direction, the reverse rotation drive amount is transmitted to the first conveyance roller 60, but the second pulley 82 rotates idly with respect to the shaft 64 by the action of the one-way clutch. As a result, the reverse rotational drive amount is not transmitted to the second transport roller 62. As a result, only the first transport roller 60 is rotated clockwise (that is, in the second rotation direction), that is, rotated so as to transport the recording paper 12 in the direction opposite to the first direction 15, and the second transport roller 62 and the second transport roller 62 are rotated. 3 The transport roller 45 is not rotated.

[Second drive transmission unit 27]
As shown in FIGS. 3 to 6, the second drive transmission unit 27 includes a first gear 78, a second gear 101, a first output gear 75, a plurality of first intermediate gears 95 meshed with each other, and a first gear 78. A single planetary gear mechanism 96 is used. The first planetary gear mechanism 96 includes a sun gear 97 (an example of the sun gear of the present invention) that meshes with the first intermediate gear 95, and a planetary gear 98 that revolves and rotates around the sun gear 97 (the planetary gear of the present invention). An example) and an arm 102 (an example of the arm of the present invention). The first gear 78, the first output gear 75, and the plurality of first intermediate gears 95 are examples of the first transmission unit of the present invention. The second gear 101 is an example of the second transmission portion of the present invention and is also an example of the second gear of the present invention.

  The first gear 78 is provided on the right side of the first conveyance path 65 in the shaft 34 of the first conveyance roller 60. When the first transport roller 60 rotates, the first gear 78 also rotates. That is, the first gear 78 is provided coaxially with the first transport roller 60 and rotates integrally with the first transport roller 60. As a result, a rotational driving force is applied from the first gear 78 to the first output gear 75 via the switching gear 51 of the switching unit 30 described later.

  The first output gear 75 meshes with the switching gear 51, the gear provided on the rearmost side of the first intermediate gear 95, and the sun gear 109 of the second planetary gear mechanism 103 of the fourth drive transmission unit 28 described later. Yes. The first output gear 75 is engaged with the switching gear 51 when the switching gear 51 is located at the second drive transmission position, as will be described later, and the rotational driving force is transmitted from the first gear 78. (See FIG. 7B).

  The first intermediate gears 95 are generally arranged in the front-rear direction 8 while being engaged with each other. In the present embodiment, an even number of first intermediate gears 95 are arranged. In FIG. 6, four first intermediate gears 95 are drawn for convenience, but it goes without saying that the number is not limited to four. The first intermediate gear 95 arranged at the foremost side meshes with the sun gear 97 of the first planetary gear mechanism 96. As described above, the rotational driving force of the first gear 78 is transmitted to the sun gear 97 via the first output gear 75 and the first intermediate gear 95.

  The sun gear 97 is rotatably supported by the frame of the printer unit 11 or the like. One end of the arm 102 is attached to the thrust surface of the sun gear 97. As a result, the arm 102 rotates coaxially with the sun gear 97. A planetary gear 98 is rotatably supported on the other end of the arm 102. The planetary gear 98 is meshed with the sun gear 97. Accordingly, the planetary gear 98 rotates while being supported by the arm 102 and revolves around the outer periphery of the sun gear 97 in the rotational direction of the sun gear 97 while meshing with the sun gear 97.

  The second gear 101 can mesh with the planetary gear 98. The positional relationship among the sun gear 97, the planetary gear 98, and the second gear 101 will be described later.

  Hereinafter, the drive transmission by the second drive transmission unit 27 will be described with reference to FIG. When the conveyance motor 71 (see FIGS. 3 to 5) is reversed, the first conveyance roller 60 and the first gear 78 rotate clockwise (that is, in the second rotation direction). Here, between the first gear 78 and the sun gear 97, the switching gear 51, the first output gear 75, and the even number of first intermediate gears 95, that is, the even number of gears are meshed with each other in a row. It is connected. For this reason, when the 1st gear 78 rotates clockwise, the sun gear 97 rotates counterclockwise, ie, the direction of the arrow 99 (an example of the 3rd rotation direction of this invention). That is, the sun gear 97 is rotated by the rotational driving force of the first gear 78.

  When the sun gear 97 rotates counterclockwise, the planetary gear 98 revolves around the sun gear 97 in the direction of the arrow 99. Thereby, the planetary gear 98 is connected to the second gear 101 and meshes with each other. That is, the third rotation direction of the present invention is the direction in which the planetary gear 98 meshes with the second gear 101, that is, the direction of the arrow 99.

  The second gear 101 is provided at the right end of the shaft 64 of the second transport roller 62 (see FIGS. 3 to 5), and rotates integrally with the second transport roller 62. When the planetary gear 98 and the second gear 101 are connected and meshed with each other, the revolution of the planetary gear 98 is stopped and the rotation (rotation) of the planetary gear 98 is started. The direction of rotation of the planetary gear 98 is clockwise. Therefore, when the planetary gear 98 rotates, the second gear 101, that is, the second conveying roller 62, which is connected and meshed with the planetary gear 98, rotates counterclockwise (that is, in the first rotation direction), that is, the recording sheet. 12 is rotated in a direction in which it is conveyed in a direction opposite to the first direction 15.

  The rotational driving force of the second conveying roller 62 counterclockwise (that is, in the first rotation direction) is transmitted to the third conveying roller 45 via the third pulley 84, the third belt 86, and the fourth pulley 85. . As a result, the third conveyance roller 45 also rotates counterclockwise (that is, in the first rotation direction), that is, in the direction in which the recording paper 12 is conveyed in the direction opposite to the first direction 15.

  On the other hand, when the transport motor 71 rotates forward, the first gear 78 rotates clockwise, and the sun gear 97 to which the rotational driving force is transmitted from the first gear 78 also rotates clockwise, It rotates in the direction of arrow 100 (an example of the fourth rotation direction of the present invention). As a result, the planetary gear 98 revolves around the sun gear 97 in the direction of the arrow 100. As a result, the planetary gear 98 is separated from the second gear 101. For this reason, the second transport roller 62 and the third transport roller 45 are not rotated by the second drive transmission unit 27.

  As described above, the second drive transmission unit 27 transmits the rotational driving force of the first transport roller 60 in the second rotational direction (an example of the second rotational drive force of the present invention) to the second transport roller 62. On the other hand, the second drive transmission unit 27 does not transmit the rotational driving force in the first rotation direction of the first transport roller 60 (an example of the first rotational drive force of the present invention) to the second transport roller 62.

  When the conveyance motor 71 rotates in the forward direction, as described above, the forward driving force of the conveyance motor 71 is increased by the first drive transmission unit 26 by the second conveyance roller 62 and the third drive transmission unit 33. 3 is transmitted to the transport roller 45. As a result, when the transport motor 71 rotates in the forward direction, the transport rollers 60, 62, 45 rotate to transport the recording paper 12 in the first direction 15. That is, the first conveyance roller 60 is rotated counterclockwise (that is, in the first rotation direction), and the second conveyance roller 62 and the third conveyance roller 45 are rotated in the clockwise direction (that is, in the second rotation direction).

[Fourth drive transmission unit 28]
As shown in FIGS. 3 to 6, the fourth drive transmission unit 28 includes a second planetary gear mechanism 103, a forward meshing gear 104, a reverse meshing gear 105, and a plurality of second intermediate gears 106 meshed with each other, A third intermediate gear 107 and a third gear 108 are included. The second planetary gear mechanism 103 includes a sun gear 109 that meshes with the first output gear 75, two planetary gears 110 and 111 that revolve and rotate around the sun gear 109, and two arms 112 and 113. Yes.

  The sun gear 109 is rotatably supported by the frame of the printer unit 11 or the like. The sun gear 109 is driven by the first output gear 75 of the second drive transmission unit 26 and rotates. That is, like the second drive transmission unit 27, the third drive transmission unit 28 is driven and transmitted from the first gear 78 when the switching gear 51 is located at the second drive transmission position (FIG. 7 ( B)).

  One end of the arms 112 and 113 is attached to the thrust surface of the sun gear 109. Thereby, the arms 112 and 113 rotate coaxially with the sun gear 97. A planetary gear 110 is rotatably supported on the other end of the arm 112. A planetary gear 111 is rotatably supported on the other end of the arm 113. The planetary gears 110 and 111 are meshed with the sun gear 109. With the above configuration, the planetary gear 110 rotates while being supported by the arm 112 and revolves in the rotational direction of the sun gear 109 while meshing with the sun gear 109. Further, by being configured as described above, the planetary gear 111 rotates while being supported by the arm 113 and revolves in the rotational direction of the sun gear 109 while meshing with the sun gear 109.

  The planetary gear 110 can mesh with the forward meshing gear 104. The planetary gear 111 can mesh with the reverse meshing gear 105. The reverse meshing gear 105 is meshed with the normal meshing gear 104. In addition to the reverse meshing gear 105, the forward meshing gear 104 is meshed with the second intermediate gear 106 arranged on the rearmost side.

  The second intermediate gears 106 are arranged approximately in the front-rear direction 8 while being engaged with each other. In the present embodiment, an even number of second intermediate gears 106 are arranged. In FIG. 7, four second intermediate gears 106 are drawn for convenience, but it is needless to say that the number is not limited to four. A third intermediate gear 107 is provided coaxially with the second intermediate gear 106 arranged on the foremost side. The third intermediate gear 107 rotates integrally with the second intermediate gear 106 around a shaft 79 coaxial with the second intermediate gear 106. The third intermediate gear 107 is meshed with the third gear 108. The third gear 108 is disposed coaxially with the fourth transport roller 68 and can rotate integrally with the fourth transport roller 68.

  Hereinafter, the drive transmission by the third drive transmission unit 28 will be described with reference to FIG. When the conveyance motor 71 is rotated forward, the first conveyance roller 60 and the first gear 78 rotate counterclockwise (that is, in the first rotation direction), the switching gear 51 rotates clockwise, and the first output gear. 75 rotates counterclockwise. Then, the sun gear 109 rotates clockwise, that is, in the direction of the arrow 114. As a result, the arms 112 and 113 also rotate in the direction of the arrow 114, so that the planetary gear 110 meshes with the forward meshing gear 104 and the planetary gear 111 is separated from the reverse meshing gear 105. Then, the planetary gear 111 meshed with the forward meshing gear 104 rotates counterclockwise. Thereby, the forward meshing gear 104 rotates clockwise.

  Here, an even number of second intermediate gears 106 are connected in a row between the forward meshing gear 104 and the third gear 108 in a state of being meshed with each other. The third intermediate gear 107 is not included in the above number because it rotates integrally with the second intermediate gear 106 coaxially. As described above, when the forward meshing gear 104 rotates clockwise, the third gear 108 and the fourth transport roller 68 rotate counterclockwise. That is, when the conveyance motor 71 is rotated forward, the fourth conveyance roller 68 rotates counterclockwise (that is, in the first rotation direction).

  On the other hand, when the conveyance motor 71 is reversed, the first conveyance roller 60 and the first gear 78 rotate clockwise (that is, in the second rotation direction), and the switching gear 51 rotates counterclockwise to generate the first output. The gear 75 rotates clockwise. Then, the sun gear 109 rotates counterclockwise, that is, in the direction of the arrow 115. As a result, the arms 112 and 113 also rotate in the direction of the arrow 115, so that the planetary gear 110 is separated from the forward meshing gear 104 and the planetary gear 111 is meshed with the reverse meshing gear 105. Then, the planetary gear 111 meshed with the reverse meshing gear 105 rotates clockwise, whereby the reverse meshing gear 105 rotates counterclockwise.

  Here, between the reverse meshing gear 105 and the third gear 108, the forward meshing gear 104 and the even number of second intermediate gears 106, that is, the odd number of gears, are connected in a row in a state where they are meshed with each other. Yes. From the above, when the reverse meshing gear 105 rotates counterclockwise, the third gear 108 and the fourth transport roller 68 also rotate counterclockwise. That is, even if the conveyance motor 71 is reversed, the fourth conveyance roller 68 rotates counterclockwise (that is, in the first rotation direction).

  From the above, the third drive transmission unit 28 records both the forward and reverse driving forces of the first conveying roller 60, that is, both the counterclockwise rotational driving force and the clockwise rotational driving force in the second rotational direction. The direction in which the sheet 12 is conveyed in the second direction 16, that is, the rotational driving force in the first rotation direction is transmitted to the fourth conveyance roller 68.

[Feeding drive transmission unit 29]
As shown in FIGS. 3 to 6, the feeding drive transmission unit 29 is attached to the second output gear 88, the fourth intermediate gear 89, the fourth belt 90, the two fifth intermediate gears 91, and the shaft 93. The sixth intermediate gear 92, the third planetary gear mechanism 120, the sixth intermediate gear 121, the seventh intermediate gear 122, the fifth belt 94, and the feeding pulley 123 coaxial with the feeding roller 25 are configured. The third planetary gear mechanism 120 includes a sun gear 124 that rotates integrally with the shaft 93 around the shaft 93, a planetary gear 125 that revolves and rotates around the sun gear 124, and an arm 126.

  The second output gear 88 is meshed with the fourth intermediate gear 89. Further, the second output gear 88 is engaged with the switching gear 51 when the switching gear 51 is located at the fourth drive transmission position, as will be described later, and the rotational driving force is transmitted from the first gear 78. (See FIG. 7C). In the present embodiment, an even number (specifically, two) fourth intermediate gears 89 are prepared. The front intermediate gear 89 is disposed coaxially with the rear fifth intermediate gear 91 out of the two fifth intermediate gears 91.

  An endless annular fourth belt 90 is bridged between the two fifth intermediate gears 91. Specifically, the fourth belt 90 is stretched over two pulleys that are arranged adjacent to each of the two fifth intermediate gears 91 and rotate coaxially and integrally with the fifth intermediate gear 91. Yes.

  The fifth intermediate gear 91 disposed on the front side of the two fifth intermediate gears 91 is meshed with the sixth intermediate gear 92. The sun gear 124 and the fifth intermediate gear 91 of the third planetary gear mechanism 120 rotate together with the shaft 93 around the shaft 93. One end of an arm 126 is attached to the thrust surface of the sun gear 124. As a result, the arm 126 rotates about the shaft 93. A planetary gear 125 is rotatably supported at the other end of the arm 126. The planetary gear 125 is meshed with the sun gear 124. With the configuration described above, the planetary gear 125 rotates while being supported by the arm 126 and revolves around the sun gear 124 in the rotational direction of the sun gear 124 while meshing with the sun gear 124.

  The seventh intermediate gear 121 is disposed at a position where it can mesh with the planetary gear 125. The eighth intermediate gear 122 is meshed with the seventh intermediate gear 121. An endless annular fifth belt is provided between the eighth intermediate gear 122 (specifically, a pulley disposed adjacent to the eighth intermediate gear 122 and coaxially and integrally rotated with the eighth intermediate gear 122) and the feed pulley 123. 94 is laid. The feed roller 25 and the feed pulley 123 rotate coaxially and integrally.

  Hereinafter, the drive transmission by the feed drive transmission unit 29 will be described with reference to FIG. When the conveyance motor 71 is reversed, the first conveyance roller 60 and the first gear 78 rotate clockwise (that is, in the second rotation direction). When the first gear 78 is rotated clockwise, the switching gear 51 is rotated counterclockwise, the second output gear 88 is rotated clockwise, and the fourth intermediate gear 89 is rotated counterclockwise. Two fifth intermediate gears 91 are rotated clockwise.

  When the fifth intermediate gear 91 is rotated clockwise, the sixth intermediate gear 92 and the sun gear 124 that is coaxial with the sixth intermediate gear 92 are rotated counterclockwise. When the sun gear 124 rotates counterclockwise, that is, in the direction of the arrow 127, the planetary gear 125 revolves around the sun gear 124 in the direction of the arrow 127. Accordingly, the planetary gear 125 is connected to and meshed with the seventh intermediate gear 121. When the planetary gear 125 and the sixth intermediate gear 121 are connected and meshed, the planetary gear 125 stops rotating and the planetary gear 125 starts rotating (rotating). The direction of rotation of the planetary gear 125 is clockwise. Therefore, when the planetary gear 125 rotates, the seventh intermediate gear 121 meshed with the planetary gear 125 rotates counterclockwise.

  When the seventh intermediate gear 121 rotates counterclockwise, the seventh intermediate gear 122 and the feeding pulley 123 rotate clockwise. When the feeding pulley 123 is rotated clockwise, the feeding roller 25 is also rotated clockwise (that is, in the second rotation direction). When the feeding roller 25 is rotated clockwise (that is, in the second rotation direction), the recording paper 12 that is placed on the feeding tray 20 and is in contact with the feeding roller 25, that is, the uppermost side. The recording paper 12 that is placed is fed toward the first transport roller 60.

  On the other hand, when the conveyance motor 71 is rotated forward, the sun gear 124 is rotated clockwise, that is, in the direction of the arrow 128 when the conveyance motor 71 is reversed. As a result, the planetary gear 125 revolves around the sun gear 124 in the direction of the arrow 128. As a result, the planetary gear 125 is separated from the sixth intermediate gear 121. As described above, when the conveying motor 71 is rotated forward, the rotational driving force is not transmitted from the conveying motor 71 to the feeding roller 25, and the feeding roller 25 does not rotate.

[Switching unit 30]
As shown in FIGS. 3 to 7, the switching unit 30 includes a switching gear 51, coil springs 56 and 57, and a switching lever 55.

  As shown in FIG. 7, the switching gear 51 is meshed with the first gear 78. As a result, the switching gear 51 rotates with the driving force applied from the conveying motor 71. In addition, the switching gear 51 is at least a first drive transmission position that is the position shown in FIG. 7A along the left-right direction 9 while maintaining meshing with the first gear 78, and FIG. ) Can be moved to the second drive transmission position. The first drive transmission position is located on the left side of the second drive transmission position. Both the first drive transmission position and the second drive transmission position are located on the right side of the first conveyance path 65.

  As shown in FIG. 7A, when the switching gear 51 is located at the first drive transmission position, the switching gear 51 is connected, that is, meshed with the first gear 78 and the fourth intermediate gear 88. At this time, the switching gear 51 is not meshed with the first output gear 75. Thereby, the rotational driving force transmitted from the conveyance motor 71 to the switching gear 51 via the first gear 78 is transmitted to the feeding drive transmission unit 29.

  As shown in FIG. 7B, when the switching gear 51 is located at the second drive transmission position, the switching gear 51 is connected, that is, meshed with the first gear 78 and the first output gear 75. At this time, the switching gear 51 is not meshed with the fourth intermediate gear 78. Accordingly, the rotational driving force transmitted from the transport motor 71 to the switching gear 51 via the first gear 78 is transmitted to the second drive transmission unit 27 and the third drive transmission unit 28.

  As shown in FIG. 7, the right side of the switching gear 51 can contact the switching lever 55. Then, the carriage 40 of the recording unit 24 can come into contact with the switching lever 55 from the left side. Further, a coil spring 56 is attached to the switching lever 55. The switching lever 55 and the coil spring 56 are disposed along the axial direction of the switching gear 51. One end of the coil spring 56 is attached to the right side of the switching lever 55, and the other end is attached to a frame (not shown) of the printer unit 11. Accordingly, the switching lever 55 is biased by the coil spring 56 from the second drive transmission position side to the first drive transmission position side, that is, the left side. A coil spring 57 is attached to the switching gear 51 at a position opposite to the coil spring 56. Thus, the switching gear 51 is urged by the coil spring 57 from the first drive transmission position side to the second drive transmission position side, that is, the right side. The urging force of the coil spring 56 is larger than the urging force of the coil spring 57. Therefore, the switching gear 51 and the switching lever 55 are urged from the second drive transmission position side toward the first drive transmission position side, that is, to the left side.

  The switching gear 51 located at the first drive transmission position is restrained from being moved by the biasing force of the coil spring 56 from the second drive transmission position to the first drive transmission position side (that is, to the left side) by a stopper (not shown). The Thereby, the switching gear 51 can remain at the second drive transmission position. When the switching lever 55 is pushed by the carriage 40 and moved to the right side of the first drive transmission position while the switch gear 51 is located at the second drive transmission position, the switch gear 51 is released from being stopped by the stopper. Then, it moves from the first drive transmission position (see FIG. 7A) to the second drive transmission position (see FIG. 7B). The stopper stops the movement of the switching gear 51 that moves to the right at the first drive transmission position and the second drive transmission position, while the stopper stops the movement of the switching gear 51 that moves to the left. It is comprised so that it may not stop in 2 drive transmission positions.

  The switching gear 51 moved to the second drive transmission position is a stopper (not shown) having the same configuration as that of the stopper provided at the second drive transmission position, as in the case of being located at the first drive transmission position. Thus, the movement by the biasing force of the coil spring 56 from the fourth drive transmission position to the first drive transmission position side (that is, to the left side) is restrained. Thereby, the switching gear 51 can remain at the second drive transmission position.

  When the switching gear 51 is positioned at the fourth drive transmission position, if the switching lever 55 is pushed by the carriage 40 and moved further to the right side than the second drive transmission position, the switching gear 51 is prevented from being stopped by the stopper. To be released. In this state, when the carriage 40 moves to the left side, the switching gear 51 is moved from the second drive transmission position to the first drive transmission position by the biasing force of the coil spring 56.

  As described above, the switching unit 30 switches whether to transmit the driving force from the first conveyance roller 60 to the second drive transmission unit 27 and the fourth drive transmission unit 28 or the feeding drive transmission unit 29. Specifically, when the switching gear 51 is located at the second drive transmission position, the switching unit 30 transmits the drive from the first transport roller 60 to the second drive transmission unit 27 and the third drive transmission unit 28. On the other hand, the switching unit 30 does not transmit the drive from the first transport roller 60 to the second drive transmission unit 27 when the switching gear 51 is located at the first drive transmission position. Note that the switching unit 30 transmits the drive from the first conveying roller 60 to the feeding drive transmission unit 29 when the switching gear 51 is located at the fourth drive transmission position.

[Positional relationship between the sun gear 97, the planetary gear 98, and the second gear 101]
In the present embodiment, the sun gear 97, the planetary gear 98, and the second gear 101 are arranged so as to satisfy the positional relationship described below. That is, as shown in FIG. 9B, the rotation center 116 of the sun gear 97 is located on the opposite side of the rotation center 130 of the planetary gear 98 with respect to the common normal line 119. Here, the common normal line 119 refers to the tooth surface 117 (see FIG. 10) of the planetary gear 98 and the tooth surface 118 of the second gear 101 (see FIG. 10) when the planetary gear 98 and the second gear 101 are engaged. ). Specifically, the tooth surface 117 of the planetary gear 98 (see FIG. 10) and the tooth surface 118 of the second gear 101 (see FIG. 10) when the second gear 101 that has been transmitted through the first drive transmission unit 26 rotates. 10)).

  The common normal line 119 will be described in detail below. As shown in FIG. 6, when the conveyance motor 71 is reversed, the sun gear 97 driven and transmitted from the second drive transmission unit 27 rotates counterclockwise, that is, in the direction of the arrow 99, and the planetary gear 98 is rotated. Meshes with the second gear 101. 9B, the planetary gear 98 rotates clockwise, that is, in the direction of the arrow 131. Then, the tooth surface 117 of the planetary gear 98 rotating in the direction of the arrow 131 comes into contact with the tooth surface 118 of the second gear 101 whose rotation is stopped, as shown in FIG.

  On the other hand, as shown in FIG. 6, when the conveyance motor 71 is rotated forward, the sun gear 97 driven and transmitted from the second drive transmission unit 27 rotates clockwise, that is, in the direction of the arrow 100. However, before the sun gear 97 rotates in the direction of the arrow 100, the second gear 101 driven and transmitted from the first drive transmission unit 26 rotates clockwise, that is, in the direction of the arrow 134 (see FIG. 9B). There is a case. Then, as shown in FIG. 10, the tooth surface 118 of the second gear 101 abuts on the tooth surface 117 of the planetary gear 98.

  This is because the first drive transmission unit 26 uses the second belt 83 with a relatively small transmission timing loss, whereas the second drive transmission unit 27 has a relatively large transmission timing loss. It is because it is comprised from the gear of this. When there are a plurality of gears, backlash occurs by the amount of the plurality of gears. For example, when driving force is transmitted from the first gear 78 to the planetary gear 98, backlash occurs between the gears arranged between the first gear 78 and the planetary gear 98. That is, there is a possibility that the planetary gear 98 is not driven at the timing when the first gear 78 is driven. Then, when the transport motor 71 rotates in the forward direction, the planetary gear 98 starts rotating after the first drive transmission unit 26 rotates the second gear 101 first.

  As described above, the tooth surface 117 of the planetary gear 98 and the tooth surface 118 of the second gear 101 abut in the state shown in FIG. At this time, the normal line of the tooth surface 117 and the normal line of the tooth surface 118 are the same line. This same line is the common normal 119.

  In FIG. 10, a common tangent 137 is shown. Specifically, the common tangent 137 is a common tangent of the reference circles 138 and 139 of the planetary gear 98 and the second gear 101. The angle θ1 between the common tangent line 137 and the common normal line 119 is the same as the angle θ2 of the pressure angle between the planetary gear 98 and the second gear 101. In this embodiment, the planetary gear 98 and the second gear 101 have a pressure angle of θ2 of 20 degrees, that is, an angle θ1 formed by the common normal 119 and the common tangent 137 is 20 degrees. It is configured as follows. Of course, the angle θ1 (angle θ2) may be other than 20 degrees.

  As described above, when the rotation center 116 of the sun gear 97 is located on the opposite side of the rotation center 130 of the planetary gear 98 with respect to the common normal line 119, the forward / reverse rotation of the transport motor 71 is involved. Instead, the planetary gear 98 is always subjected to a force 133 that tries to be separated from the second gear 101. Hereinafter, a detailed description will be given with reference to FIG. 9B and FIG.

  When the conveying motor 71 is reversed, as described above, the tooth surface 117 of the planetary gear 98 rotated in the direction of the arrow 131 comes into contact with the tooth surface 118 of the second gear 101 whose rotation is stopped. That is, the tooth surface 117 of the planetary gear 98 presses the tooth surface 118 of the second gear 101 whose rotation is stopped. At this time, an action force 132 (see FIG. 10) is applied to the second gear 101 from the planetary gear 98, and a reaction force 133 is applied to the planetary gear 98 from the second gear 101. On the other hand, when the transport motor 71 is rotated forward, the tooth surface 118 of the second gear 101 rotated in the direction of the arrow 134 contacts the tooth surface 117 of the planetary gear 98 as described above. That is, the tooth surface 118 of the second gear 101 presses the tooth surface 117 of the planetary gear 98. At this time, the same force as the reaction force 133 described above is applied to the planetary gear 98 from the second gear 101 as an action force. As described above, the force 133 acts on the planetary gear 98 regardless of whether the conveyance motor 71 is forward or reverse.

  As shown in FIG. 9B, a common normal line 119 that is an extension of the force 133 passes between the rotation center 116 of the sun gear 97 and the rotation center 130 of the planetary gear 98. With this force 133, the planetary gear 98 tries to rotate the sun gear 97 in the direction of the arrow 100. Therefore, the planetary gear 98 to which the force 133 is applied tries to revolve around the sun gear 97 in the direction of the arrow 100. That is, when the rotation center 116 of the sun gear 97 is located on the opposite side of the rotation center 130 of the planetary gear 98 with respect to the common normal line 119, the planetary gear 98 to which the force 133 is applied is the second gear. Trying to move away from 101.

  As described above, in the configuration of FIG. 9B, when the transport motor 71 is rotated forward, that is, when the planetary gear 98 is to be separated from the second gear 101, the planetary gear 98 is reliably separated from the second gear 101. Can be separated.

  On the other hand, unlike the present embodiment, the case where the rotation center 116 of the sun gear 97 is located on the same side as the rotation center 130 of the planetary gear 98 with respect to the common normal line 119 will be described. As shown in FIG. 9A, the common normal line 119 that is an extension line of the force 133 does not pass between the rotation center 116 of the sun gear 97 and the rotation center 130 of the planetary gear 98. By this force 133, the planetary gear 98 tries to rotate the sun gear 97 in the direction of the arrow 99. Therefore, the planetary gear 98 to which the force 133 is applied tries to revolve around the sun gear 97 in the direction of the arrow 99. That is, when the rotation center 116 of the sun gear 97 is located on the same side as the rotation center 130 of the planetary gear 98 with respect to the common normal line 119, the planetary gear 98 to which the force 133 is applied is the second gear. It tries to move in the direction of meshing with 101.

  As described above, in the configuration of FIG. 9A, even when the transport motor 71 is rotated forward, that is, when the planetary gear 98 should be separated from the second gear 101, the planetary gear 98 is in the second gear 101. There is a risk that it will not be separated. The reason is as follows. When the transport motor 71 is rotated forward, the sun gear 97 rotates in the direction of the arrow 100. As a result, the planetary gear 98 is applied with a force in a direction to move away from the second gear 101 from the sun gear 97. However, if the force 133 is greater than the force, the planetary gear 98 may not be separated from the second gear 101. On the other hand, as described above, in the present embodiment, the planetary gear 98 can be reliably separated from the second gear 101 when the transport motor 71 is reversed.

  In the above description, the sun gear 97 and the planetary gear 98 of the first planetary gear mechanism 96 and the second gear 101 are arranged so as to satisfy the positional relationship as shown in FIG. However, it is not limited to the first planetary gear mechanism 96 that the gears are arranged to satisfy the positional relationship. For example, the sun gear 124 and the planetary gear 125 of the third planetary gear mechanism 120 and the sixth intermediate gear 121 may be arranged so as to satisfy the above positional relationship. That is, the rotation center of the sun gear 124 may be located on the opposite side of the rotation center of the planetary gear 125 with respect to the common normal. Here, the common normal line is a normal line of the tooth surfaces of both gears that are in contact with each other when the planetary gear 125 and the sixth intermediate gear 121 are engaged with each other.

[Leaf spring 135]
As shown in FIG. 9B, when the rotation center 116 of the sun gear 97 is located on the opposite side of the rotation center 130 of the planetary gear 98 with respect to the common normal line 119, the transport motor 71 rotates in the reverse direction. Then, the sun gear 97 rotates in the direction of the arrow 99. As a result, a force 136 is applied to the planetary gear 98 in a direction that causes the sun gear 97 to mesh with the second gear 101. However, when the force 133 is larger than the force 136, the planetary gear 98 may be separated from the second gear 101.

  Therefore, in this embodiment, as shown in FIGS. 3 and 4, a leaf spring 135 (an example of the friction resistance member of the present invention) is provided. The leaf spring 135 is generally U-shaped bent at two locations. The leaf spring 135 sandwiches the planetary gear 98 from the outside of both thrust surfaces of the planetary gear 98. As a result, a biasing force is applied to the planetary gear 98 from the outside of the thrust surface toward the center of the planetary gear 98. As a result, a frictional resistance against the rotation of the planetary gear 98 is generated.

  For example, when the force 133 acts on the planetary gear 98 as a force for rotating the planetary gear 98 in the direction opposite to the arrow 131, the frictional resistance is a resistance against the force 133. That is, the frictional resistance is a resistance against the force 133 that tries to separate the planetary gear 98 from the second gear 101. As a result, the above-described separation of the planetary gear 98 from the second gear 101, that is, the separation of the planetary gear 98 from the second gear 101 due to the force 133 being larger than the force 136 can be prevented.

[Effect of the embodiment]
When the sun gear 97, the planetary gear 98, and the second gear 101 are arranged in the positional relationship as in the present embodiment, a force 133 that tries to separate from the second gear 101 acts on the planetary gear 98. . That is, no force in the direction to mesh with the second gear 101 acts on the planetary gear 98. Therefore, when the sun gear 97 rotates in the fourth rotation direction, that is, in the direction of the arrow 100 with the planetary gear 98 and the second gear 101 engaged, the planetary gear 98 is easily separated from the second gear 101.

  Therefore, according to the present embodiment, the planetary gear 98 should be separated from the second gear 101, that is, the second gear 101 should rotate with the driving force transmitted through the first drive transmission unit 26. In a state where the driving force is not transmitted through the second drive transmission unit 27 and should not be rotated, the second gear 101 erroneously transmits the driving force through the second drive transmission unit 27 and rotates. Can be prevented. That is, in this embodiment, the meshing state between the planetary gear 98 and the second gear 101 can be appropriately released.

  In the present embodiment, the first drive transmission unit 26 transmits the rotational driving force in the first rotation direction from the first conveyance roller 60 to the second conveyance roller 62 via the second belt 83, while the one-way clutch Due to the presence, the rotational driving force in the second rotational direction is not transmitted to the second transport roller 62. As described above, the present embodiment is a suitable configuration for realizing the function of the first drive transmission unit 26.

  When the sun gear 97 rotates in the third rotation direction, that is, in the direction of the arrow 99 by the rotation of the first transport roller 60 in the second rotation direction, the planetary gear 98 revolves in the direction of the arrow 99 and the second gear. Engage with 101. Thereafter, the planetary gear 98 rotates in conjunction with the rotation of the sun gear 97. As a result, the second gear 101 rotates. However, when the sun gear 97, the planetary gear 98, and the second gear 101 are arranged in the positional relationship as shown in FIG. 9B, when the planetary gear 98 is rotated as described above, the planetary gear 98 is rotated. The force 133 acts in a direction away from the second gear 101. If the planetary gear 98 is separated from the second gear 101 by the action of the force 133, the second gear 101 to be rotated cannot rotate when the first transport roller 60 rotates in the second rotation direction.

  Therefore, in this embodiment, a leaf spring 135 is provided. As a result, the planetary gear 98 is subjected to a force in the direction from the planetary gear 98 to the second gear 101, that is, a force to be separated from the second gear 101 by a frictional resistance force generated during rotation. When the force in the direction from the planetary gear 98 to the second gear 101 is larger than the force in the direction from the second gear 101 to the planetary gear 98, the planetary gear 98 is erroneously separated from the second gear 101. Can be prevented.

[Modification 1]
In the above-described embodiment, as shown in FIG. 10, the planetary gear 98 and the second gear 101 are engaged, that is, the tooth surface 117 of the planetary gear 98 is in contact with the tooth surface 118 of the second gear 101. In this state, the tooth top 142 of the planetary gear 98 is located on the shaft 64 (see FIG. 9) side of the second gear 101 relative to the reference circle 139 of the second gear 101, that is, on the radially inner side of the second gear 101. It was.

  On the other hand, in Modification 1, as shown in FIG. 12, in the state where the planetary gear 98 and the second gear 101 are engaged, the tooth top 142 of the planetary gear 98 is the reference circle of the second gear 101. It is located on the opposite side to the shaft 64 (see FIG. 9) of the second gear 101 from 139, that is, on the outer side in the radial direction of the second gear 101.

  In the first modification, in a state where the planetary gear 98 and the second gear 101 are engaged with each other, the top portion 142 of the teeth of the planetary gear 98 is set outside the reference circle 139 of the second gear 101 in the radial direction of the second gear 101. For this purpose, a stop member 140 is provided on the second gear 101. The restraining member 140 is formed so as to fill the space 146 at the bottom between the teeth of the second gear 101. In the present embodiment, the contact surface of the restraining member 140 with the planetary gear 98 is a surface along the reference circle 139 of the second gear 101. The contact surface of the restraining member 140 may be closer to the tooth top portion 145 of the second gear 101 than the reference circle 139 of the second gear 101. As described above, the restraining member 140 is provided between the teeth of the second gear 101 and between the top 145 of each tooth and the reference circle 139, and the planetary gear 98 meshed with the second gear 101. The tooth top portion 142 is prevented from entering the inside of the second gear 101 in the radial direction.

  In the first modification, the restraining member 140 is provided on the second gear 101, but the restraining member 140 may be provided on the planetary gear 98. In the first modification, the restraining member 140 is provided for the purpose of restraining the top portion 141 of the tooth of the planetary gear 98 engaged with the second gear 101 from entering the inside of the second gear 101 in the radial direction. Other than the arrangement of the restraining member 140, the above object may be achieved by, for example, the configuration of Modification 2 described later.

  According to the first modification, the planetary gear 98 can be easily separated from the second gear 101.

  Further, according to the first modification, for example, one that supports the shaft 64 that is the rotation center of the second gear 101 or one that supports the shaft that is the rotation center 116 of the sun gear 97 (for example, the frame of the multifunction machine 10). ) May be deformed, the rotation center of the second gear 101 and the rotation center 116 of the sun gear 97 may approach each other. However, since the stop member 140 is formed, the contact position between the planetary gear 98 and the second gear 101 is outside the reference circle 139 of the second gear 101 in the radial direction. Therefore, according to the first modification, even when the rotation center of the second gear 101 and the rotation center of the sun gear 97 approach each other, the planetary gear 98 can be easily separated from the second gear 101.

[Modification 2]
As shown in FIG. 13, in the second modification, a contacted portion 143 is formed on the arm 102. In the arm 102, the contacted portion 143 is formed as a convex portion on the opposite side of the planetary gear 98 with respect to the sun gear 97. On the other hand, a contact portion 144 that contacts the contacted portion 143 is formed on the frame of the multifunction machine 10 at a position facing the contacted portion 143.

  As shown in FIG. 13A, the contacted portion 143 contacts the contact portion 144 in a state where the planetary gear 98 and the second gear 101 are engaged. When the contacted portion 143 contacts the contact portion 144, the planetary gear 98 is prevented from further revolving in the direction of the arrow 99 from the state of FIG.

  On the other hand, as shown in FIG. 13B, when the planetary gear 98 revolves in the direction of the arrow 100, the planetary gear 98 and the second gear 101 are separated from each other. In this state, the contacted portion 143 is separated from the contact portion 144.

  According to the second modification, the contact position of the planetary gear 98 with respect to the second gear 101 is greater than the diameter of the second gear 101 than the reference circle 139 due to the contacted portion 143 and the contact portion 144 being in contact with each other. It is reliably maintained outside the direction. Therefore, the planetary gear 98 can be easily separated from the second gear 101.

[Modification 3]
The present invention may be applied to an embodiment as shown in FIG. In the modification 3, the 3rd conveyance roller 45, the spur 46, and the 3rd drive transmission part 33 of the above-mentioned embodiment are mainly omitted. The second conveyance path 67 is a path extending from between the recording unit 24 and the second conveyance roller 62 to the upstream side in the first direction 15 of the first conveyance roller 60. In the case of the modification 3, the 2nd conveyance roller 62 is an example of the 2nd roller of this invention. Moreover, in the case of the modification 3, the 2nd drive transmission part 27 is an example of the 2nd drive transmission part of this invention.

DESCRIPTION OF SYMBOLS 10 ... Multifunction machine 12 ... Recording paper 15 ... 1st direction 24 ... Recording part 26 ... 1st drive transmission part 27 ... 2nd drive transmission part 60 ... 1st conveyance Roller 62 ... second transport roller 65 ... first transport path 71 ... transport motor 78 ... first gear 97 ... sun gear 98 ... planetary gear 101 ... second gear 102 ... Arm 119 ... Common normal 135 ... Leaf spring

Claims (9)

A drive source that is rotated forward and backward, and
When the drive source rotates forward, the sheet rotates in the first rotation direction, conveys the sheet in the conveyance path along the conveyance direction, and reverses the first rotation direction when the drive source reverses. A first roller that rotates in two rotation directions;
A second roller that is provided downstream of the first roller in the conveying direction and conveys the sheet by rotating;
A first drive transmission unit configured to transmit a first rotational driving force of the first roller in the first rotational direction to the second roller and not transmit a second rotational driving force in the second rotational direction to the second roller; ,
A second drive transmission unit that transmits the second rotational driving force of the first roller to the second roller and does not transmit the first rotational driving force of the first roller to the second roller. ,
The second drive transmission unit is
A first transmission unit having at least one first gear and transmitting the first rotational driving force from the first roller;
A second transmission portion having at least one second gear and transmitting the second rotational driving force from the first roller to the second roller;
A sun gear that is rotated by the rotational driving force transmitted from the first roller transmitted to the first transmission unit;
An arm that rotates coaxially with the sun gear;
A planetary gear that is rotatably supported by the arm and revolves in the direction of rotation of the sun gear while meshing with the sun gear;
The sun gear
When the second rotational driving force is transmitted from the first transmission unit, the planetary gear rotates in a third rotational direction that meshes with the second gear, and the first rotational driving force is transmitted from the first transmission unit. When transmitted, the planetary gear rotates in a fourth rotational direction away from the second gear,
The center of rotation of the sun gear is
A tooth surface of the planetary gear and a tooth surface of the second gear when the second gear rotated and transmitted through the first drive transmission unit rotates with the planetary gear and the second gear engaged. Is located on the opposite side of the center of rotation of the planetary gear ,
In a state where the above-described planetary gear and the second gear is engaged, characterized in that the top of the teeth of the planetary gear is located on the outer side in the radial direction of the second gear than the reference circle of the second gear conveyance equipment. Between the teeth of the second gear and between the top of each tooth and the reference circle, the top of the teeth of the planetary gear meshed with the second gear is in the radial direction of the second gear. The conveying device according to claim 1 , wherein a restraining member that restrains the inward entry is formed. A contact portion;
Provided on the arm, contacted with the contact portion when the planetary gear meshes with the second gear, and contacted with the contact portion separated from the contact portion when the planetary gear is separated from the second gear conveying apparatus according to claim 1 or 2, characterized in that it comprises a part, a. The first drive transmission unit includes:
A first pulley that rotates in conjunction with the rotation of the first roller;
When the first rotational driving force is transmitted, the second roller rotates in conjunction with the second roller, and when the second rotational driving force is transmitted to the second roller, Against the one-way clutch that idles,
A second pulley having the one-way clutch;
The belt according to any one of claims 1 to 3 , further comprising: a belt that spans between the first pulley and the second pulley and is capable of circumferential movement between the first pulley and the second pulley. The conveying apparatus as described. Conveying apparatus according to any one of 4 to frictional resistance to rotation of the planetary gears claim 1, further comprising a frictional resistance member for applying to the planetary gear.   A drive source that is rotated forward and backward, and
  When the drive source rotates forward, the sheet rotates in the first rotation direction, conveys the sheet in the conveyance path along the conveyance direction, and reverses the first rotation direction when the drive source reverses. A first roller that rotates in two rotation directions;
  A second roller that is provided downstream of the first roller in the conveying direction and conveys the sheet by rotating;
  A first drive transmission unit configured to transmit a first rotational driving force of the first roller in the first rotational direction to the second roller and not transmit a second rotational driving force in the second rotational direction to the second roller; ,
  A second drive transmission unit that transmits the second rotational driving force of the first roller to the second roller and does not transmit the first rotational driving force of the first roller to the second roller. ,
  The second drive transmission unit is
  A first transmission unit having at least one first gear and transmitting the first rotational driving force from the first roller;
  A second transmission portion having at least one second gear and transmitting the second rotational driving force from the first roller to the second roller;
  A sun gear that is rotated by the rotational driving force transmitted from the first roller transmitted to the first transmission unit;
  An arm that rotates coaxially with the sun gear;
  A planetary gear that is rotatably supported by the arm and revolves in the direction of rotation of the sun gear while meshing with the sun gear;
  The sun gear
  When the second rotational driving force is transmitted from the first transmission unit, the planetary gear rotates in a third rotational direction that meshes with the second gear, and the first rotational driving force is transmitted from the first transmission unit. When transmitted, the planetary gear rotates in a fourth rotational direction away from the second gear,
  The center of rotation of the sun gear is
  A tooth surface of the planetary gear and a tooth surface of the second gear when the second gear rotated and transmitted through the first drive transmission unit rotates with the planetary gear and the second gear engaged. Is located on the opposite side of the center of rotation of the planetary gear,
  The first drive transmission unit includes:
  A first pulley that rotates in conjunction with the rotation of the first roller;
  When the first rotational driving force is transmitted, the second roller rotates in conjunction with the second roller, and when the second rotational driving force is transmitted to the second roller, Against the one-way clutch that idles,
  A second pulley having the one-way clutch;
  And a belt that spans between the first pulley and the second pulley and that can move between the first pulley and the second pulley.   A drive source that is rotated forward and backward, and
  When the drive source rotates forward, the sheet rotates in the first rotation direction, conveys the sheet in the conveyance path along the conveyance direction, and reverses the first rotation direction when the drive source reverses. A first roller that rotates in two rotation directions;
  A second roller that is provided downstream of the first roller in the conveying direction and conveys the sheet by rotating;
  A first drive transmission unit configured to transmit a first rotational driving force of the first roller in the first rotational direction to the second roller and not transmit a second rotational driving force in the second rotational direction to the second roller; ,
  A second drive transmission unit that transmits the second rotational driving force of the first roller to the second roller and does not transmit the first rotational driving force of the first roller to the second roller. ,
  The second drive transmission unit is
  A first transmission unit having at least one first gear and transmitting the first rotational driving force from the first roller;
  A second transmission portion having at least one second gear and transmitting the second rotational driving force from the first roller to the second roller;
  A sun gear that is rotated by the rotational driving force transmitted from the first roller transmitted to the first transmission unit;
  An arm that rotates coaxially with the sun gear;
  A planetary gear that is rotatably supported by the arm and revolves in the direction of rotation of the sun gear while meshing with the sun gear;
  The sun gear
  When the second rotational driving force is transmitted from the first transmission unit, the planetary gear rotates in a third rotational direction that meshes with the second gear, and the first rotational driving force is transmitted from the first transmission unit. When transmitted, the planetary gear rotates in a fourth rotational direction away from the second gear,
  The center of rotation of the sun gear is
  A tooth surface of the planetary gear and a tooth surface of the second gear when the second gear rotated and transmitted through the first drive transmission unit rotates with the planetary gear and the second gear engaged. Is located on the opposite side of the center of rotation of the planetary gear,
  A transport device further comprising a friction resistance member that imparts a frictional resistance force to the planetary gear against the rotation of the planetary gear. A transport apparatus according to any one of claims 1 to 7 ;
A recording unit that is provided between the first roller and the second roller in the conveying direction and is capable of reciprocating in a main scanning direction orthogonal to the conveying direction, and that records an image on a sheet;
A switching unit that is movable in the main scanning direction by contacting the recording unit that moves in the main scanning direction, and that switches whether or not to transmit a rotational driving force to the second drive transmission unit; An image recording apparatus provided.   A drive source that is rotated forward and backward, and
  When the drive source rotates forward, the sheet rotates in the first rotation direction, conveys the sheet in the conveyance path along the conveyance direction, and reverses the first rotation direction when the drive source reverses. A first roller that rotates in two rotation directions;
  A second roller that is provided downstream of the first roller in the conveying direction and conveys the sheet by rotating;
  A first drive transmission unit configured to transmit a first rotational driving force of the first roller in the first rotational direction to the second roller and not transmit a second rotational driving force in the second rotational direction to the second roller; ,
  A second drive transmission unit for transmitting the second rotational driving force of the first roller to the second roller and not transmitting the first rotational driving force of the first roller to the second roller;
  A recording unit that is provided between the first roller and the second roller in the conveying direction and is capable of reciprocating in a main scanning direction orthogonal to the conveying direction, and that records an image on a sheet;
  A switching unit that is movable in the main scanning direction by contacting the recording unit that moves in the main scanning direction, and that switches whether or not to transmit a rotational driving force to the second drive transmission unit; Has
  The second drive transmission unit is
  A first transmission unit having at least one first gear and transmitting the first rotational driving force from the first roller;
  A second transmission portion having at least one second gear and transmitting the second rotational driving force from the first roller to the second roller;
  A sun gear that is rotated by the rotational driving force transmitted from the first roller transmitted to the first transmission unit;
  An arm that rotates coaxially with the sun gear;
  A planetary gear that is rotatably supported by the arm and revolves in the direction of rotation of the sun gear while meshing with the sun gear;
  The sun gear
  When the second rotational driving force is transmitted from the first transmission unit, the planetary gear rotates in a third rotational direction that meshes with the second gear, and the first rotational driving force is transmitted from the first transmission unit. When transmitted, the planetary gear rotates in a fourth rotational direction away from the second gear,
  The center of rotation of the sun gear is
  A tooth surface of the planetary gear and a tooth surface of the second gear when the second gear rotated and transmitted through the first drive transmission unit rotates with the planetary gear and the second gear engaged. The image recording apparatus is located on the opposite side of the rotation center of the planetary gear with respect to the common normal to the center.

Images