Conveyor

Abstract

To provide means for quickly switching a drive transmission.SOLUTION: A printer part 11 includes: a conveyance motor 102; a sun gear 92; a gear 90 that engages with the sun gear 92; a planetary gear 93 that engages with the sun gear 92; a clutch mechanism 190; and a gear 96 that can engage with the planetary gear 93; and a conveyance roller 64 to which a driving force is transmitted from the gear 96.SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The present invention relates to a conveying device that conveys a sheet. [Background technology]

[0002] 2. Description of the Related Art A conveying device for conveying a sheet is known in the art. An example of an apparatus equipped with such a conveying device is an inkjet recording apparatus that records an image on a sheet by an inkjet recording method.

[0003] In a conveying device or an inkjet recording device, in order to transmit the output of one motor to a plurality of drive units, a drive transmission is switched as disclosed in the image recording device of Patent Document 1. More specifically, a switch gear is arranged that is slidable along the axial direction of the drive gear while meshing with the drive gear to which the drive is transmitted from the motor. Also, a plurality of receiver gears for transmitting the drive to each drive unit are arranged corresponding to each sliding position of the switch gear. The switch gear is slid to mesh with each receiver gear. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-71407 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in switching the drive transmission in the image recording device disclosed in Patent Document 1, an operation must be performed to reduce the surface pressure between the gears in order to slide the switch gear. In this operation, the switch gear is reversed according to the surface pressure applied to the switch gear, so the amount of reverse rotation of the switch gear is set to be large when the surface pressure is large. In general, the more gears there are between the switch gear and the drive unit, the larger the surface pressure applied to the switch gear. Also, the more reverse rotation of the motor, the longer the time required to slide the switch gear.

[0006] The present invention has been made in consideration of the above circumstances, and has an object to provide a means capable of quickly switching the drive transmission. [Means for solving the problem]

[0007] (1) The conveying device of the present invention comprises a motor, a sun gear, a first drive transmission mechanism having a first transmission gear that transmits the driving force of the motor to the sun gear, a planetary gear that is rotatably supported on a support arm that is rotatable around the axis of the sun gear and meshes with the sun gear, a second drive transmission mechanism that transmits driving force from the first transmission gear to the sun gear and has a range in which the sun gear can rotate freely relative to the first transmission gear, a third drive transmission mechanism having a second transmission gear that can mesh with the planetary gear, and a conveying roller that conveys a sheet by rotating when driven by the third drive transmission mechanism.

[0008] When the motor rotates slightly in the other direction from a state in which rotation in one direction is transmitted to the transmission gear via the second drive transmission mechanism, the sun gear, and the planetary gear, the second drive transmission mechanism allows the sun gear to rotate freely relative to the first transmission gear, and the surface pressure from the second transmission gear causes the planetary gear to move in a direction away from the second transmission gear. The sun gear rotates freely in conjunction with the movement of the planetary gear, thereby reducing the surface pressure applied from the sun gear to the first transmission gear of the first drive transmission mechanism.

[0009] (2) Preferably, the first drive transmission mechanism includes a slide gear slidably supported on a support shaft along the axial direction and rotates when driving force is transmitted from the motor, a third transmission gear capable of meshing with the slide gear and transmitting driving force to the sun gear, and a slide mechanism for sliding the slide gear, wherein the slide mechanism slides the slide gear between a first slide position where the slide gear meshes with the third transmission gear and a second slide position where the slide gear does not mesh with the third transmission gear.

[0010] When the slide gear slides from the first slide position to the second slide position, it is preferable that the surface pressure between the slide gear and the third transmission gear is small. For example, the surface pressure between the slide gear and the third transmission gear is reduced by reversing the motor from one rotation direction to the other rotation direction. As described above, when the motor is reversed from one rotation direction to the other rotation direction, play is generated in the sun gear due to the movement of the second drive transmission mechanism and the planetary gear, so the amount of reverse rotation of the motor is reduced in order to reduce the surface pressure between the slide gear and the third transmission gear.

[0011] (3) Preferably, the device further includes a control unit for controlling the motor and the slide mechanism, and the control unit executes a rotation process for rotating the motor in reverse while the slide gear and the third transmission gear are engaged, and a slide process for controlling the slide mechanism to slide the slide gear after the rotation process is executed.

[0012] (4) Preferably, the printing apparatus has a recording head which ejects ink from nozzles toward the sheet transported by the transport roller, and further includes a printing area in which the recording head can eject ink toward the sheet, and a carriage which can move to a basic position outside the printing area, and the slide mechanism has the carriage and a protrusion which protrudes into the movement area of ​​the carriage, a lever member which moves the slide gear from the first slide position toward the second slide position by abutting against the carriage, and a biasing member which biases the slide gear from the second slide position to the first slide position.

[0013] (5) Preferably, the second drive transmission mechanism includes a key groove, provided on one of the first transmission gear or the sun gear, having a first surface and a second surface spaced apart along the circumferential direction, and a key, provided on the other of the first transmission gear or the sun gear, located between the first surface and the second surface in the circumferential direction, wherein the circumferential length of the key is shorter than the circumferential length between the first surface and the second surface.

[0014] (6) Preferably, the planetary gear is rotatably supported by a support arm rotatable about the axis of the sun gear, and a counterweight for the planetary gear is provided on the support arm.

[0015] According to the above configuration, the planetary gear easily moves in a direction away from the second transmission gear.

[0016] (7) Preferably, the planetary gear is a first planetary gear rotatably supported by the support arm, and the counterweight is a second planetary gear rotatably supported by the support arm.

[0017] (8) Preferably, the counterweight is heavier than the planetary gear.

[0018] According to the above configuration, the planetary gear is more likely to move in a direction away from the second transmission gear.

[0019] (9) Preferably, the planetary gears include a first planetary gear and a second planetary gear each rotatably supported by a support arm rotatable around an axis of the sun gear. Effect of the Invention

[0020] According to the present invention, the drive transmission can be switched quickly. [Brief description of the drawings]

[0021] [Figure 1] FIG. 1 is a perspective view of a multifunction device 10. As shown in FIG. [Diagram 2] FIG. 2 is a vertical cross-sectional view showing a schematic internal structure of the printer unit 11. As shown in FIG. [Diagram 3] FIG. 3 is a plan view of the carriage 23 and the guide rails 43 and 44. As shown in FIG. [Figure 4] FIG. 4 is a block diagram of the printer unit 11. [Diagram 5]FIG. 5 is a schematic diagram showing the configuration of the maintenance mechanism 110 and the waste ink tank 120. As shown in FIG. [Figure 6] FIG. 6 is a schematic diagram of the first transmission part 181, the third transmission part 183, the fourth transmission part 184, and the slide mechanism 170. [Figure 7] FIG. 7 is a schematic diagram of the second transmission part 182, the sixth transmission part 186, and the seventh transmission part 187. [Figure 8] FIG. 8 is a perspective view of the slide mechanism 170 and the transport roller 60 and its surroundings. [Figure 9] FIG. 9 is a perspective view of the slide mechanism 170, the feed roller 25, the transport roller 64, and the surrounding area. [Figure 10] FIG. 10 is a perspective view of the slide mechanism 170, the second transmission part 182, and the fifth transmission part 185 and their surroundings. [Figure 11] FIG. 11 is a right side view of the vicinity of the slide mechanism 170, the second transmission part 182, and the fifth transmission part 185. FIG. [Figure 12] FIG. 12 is a plan view of the slide mechanism 170. As shown in FIG. [Figure 13] FIG. 13 is a plan view of the vicinity of the holding portion 173 and the roller gear 180. As shown in FIG. [Figure 14] FIG. 14A is a perspective view showing the sun gear 92 and the planetary gears 93 and 94, and FIG. [Figure 15] FIG. 15 is a plan view of the periphery of the slide mechanism 170 when the slide gear 160 is located at the left position LP. [Figure 16] FIG. 16 is a plan view of the periphery of the slide mechanism 170 when the slide gear 160 is located at the first central position MP1. [Figure 17] FIG. 17 is a plan view of the periphery of the slide mechanism 170 when the slide gear 160 is located at the second central position MP2. [Figure 18] FIG. 18 is a plan view of the periphery of the slide mechanism 170 when the slide gear 160 is located at the right position RP. [Figure 19] FIG. 19 is a flowchart illustrating the double-sided printing process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, an embodiment of the present invention will be described. Note that the embodiment described below is merely one example of the present invention, and it goes without saying that the embodiment of the present invention can be modified as appropriate without departing from the gist of the present invention. In addition, the up-down direction 7 is defined based on the state in which the multifunction device 10 is installed so as to be usable (the state shown in FIG. 1), the front-rear direction 8 is defined with the side in which the opening 13 is provided being the near side (front), and the left-right direction 9 is defined when the multifunction device 10 is viewed from the near side (front).

[0023] [Overall configuration of multifunction device 10] As shown in Fig. 1, the multifunction device 10 is formed into a roughly rectangular parallelepiped shape. The multifunction device 10 has various functions such as a facsimile function and a printing function. The multifunction device 10 has a printer unit 11 (an example of a conveying device) at the bottom that records an image on one side of paper 12 (see Fig. 2) using an inkjet recording method. Note that the printer unit 11 may also record an image on both sides of paper 12.

[0024] 2, the printer unit 11 includes a feed unit 15, a feed tray 20, a discharge tray 21, a transport roller unit 54, and a discharge roller unit 55 in order to transport the paper 12. The printer unit 11 also includes a recording unit 24 and a platen 42 that supports the paper 12 in order to record an image on the paper 12. Furthermore, as shown in FIG. 4, the printer unit 11 includes a feed motor 101, a transport motor 102, a control unit 130, a drive force transmission mechanism 70, and a maintenance mechanism 110.

[0025] [Feed tray 20, output tray 21] 1 and 2, the feed tray 20 is inserted and removed in the front-rear direction 8 through an opening 13 formed in the front of the printer unit 11. The feed tray 20 supports a plurality of stacked sheets of paper 12. The discharge tray 21 is disposed above the feed tray 20. The discharge tray 21 supports the sheets of paper 12 discharged by the discharge roller unit 55 through the opening 13.

[0026] [Feeding section 15] 2, the feeding unit 15 includes a feeding roller 25, a feeding arm 26, and a shaft 27. The feeding roller 25 is rotatably supported on the tip side of the feeding arm 26. The feeding roller 25 rotates in a direction (i.e., forward rotation) to feed the paper 12 supported by the feeding tray 20 toward a transport path 65 described later in a transport direction 16 by forward rotation of a feeding motor 101 (see FIG. 4). The feeding arm 26 is rotatably supported by the shaft 27 supported by the frame of the printer unit 11.

[0027] [Transport Path 65] 2, a conveying path 65 and a reversing conveying path 66 through which the paper 12 passes are formed inside the printer unit 11. The conveying path 65 refers to a space defined by guide members 18, 19 opposed to each other at a predetermined distance inside the printer unit 11. The conveying direction 16 of the paper 12 in the conveying path 65 is indicated by a dashed arrow in FIG.

[0028] The conveying path 65 is composed of a curved conveying path and a straight conveying path that extends linearly. The curved conveying path is a path that makes a U-turn while extending from the bottom to the top at the rear side of the printer unit 11. The straight conveying path is a path that reaches the discharge tray 21 from the conveying roller unit 54 via the recording unit 24, the discharge roller unit 55, and the reversing roller unit 56.

[0029] The reverse conveying path 66 connects a position between the discharge roller section 55 and the reverse roller section 56 on the straight conveying path of the conveying path 65 and a position upstream of the conveying roller section 54 in the curved conveying path of the conveying path 65 in the conveying direction 16, and is a path located between the feeding section 15 and the platen 42 in the vertical direction 7.

[0030] [Transport roller section 54] As shown in FIG. 2, the transport roller unit 54 is disposed upstream of the recording unit 24 in the transport direction 16. The transport roller unit 54 includes a transport roller 60 and a pinch roller 61 that face each other. The transport roller 60 is driven by a transport motor 102 (see FIG. 4). The pinch roller 61 rotates with the rotation of the transport roller 60. The transport roller unit 54 rotates forward by the forward rotation force of the transport motor 102 being transmitted thereto. The forward rotation is a rotation in a direction in which the sandwiched paper 12 is transported in the transport direction 16. In addition, the transport roller unit 54 can rotate in a reverse direction opposite to the forward rotation by the reverse rotation force of the transport motor 102 being transmitted thereto.

[0031] [Discharge roller section 55] As shown in FIG. 2, the discharge roller unit 55 is disposed downstream of the recording unit 24 in the conveying direction 16. The discharge roller unit 55 includes a discharge roller 62 (one example of a conveying roller) and a spur 63 that face each other. The discharge roller 62 is driven by a conveying motor 102 (see FIG. 4). The spur 63 rotates with the rotation of the discharge roller 62. The forward rotation force of the conveying motor 102 is transmitted to the discharge roller unit 55, so that the discharge roller unit 55 can rotate forward to convey the sandwiched paper 12 in the conveying direction 16. The reverse rotation force of the conveying motor 102 is transmitted to the discharge roller unit 55, so that the discharge roller unit 55 can rotate in the reverse direction opposite to the forward rotation.

[0032] [Reversing roller part 56] As shown in FIG. 2, the reversing roller unit 56 is disposed downstream of the discharge roller unit 55 in the conveying direction 16. The reversing roller unit 56 includes a reversing roller 68 and a pinch roller 69 that face each other. The reversing roller 68 is driven by a conveying motor 102 (see FIG. 4). The pinch roller 69 rotates with the rotation of the reversing roller 68. The forward rotation force of the conveying motor 102 is transmitted to the reversing roller unit 56, so that the reversing roller unit 56 can rotate forward to convey the sandwiched paper 12 in the conveying direction 16. The reverse rotation force of the conveying motor 102 is transmitted to the reversing roller unit 56, so that the reverse rotation is opposite to the forward rotation.

[0033] [Transport roller 64] As shown in FIG. 2, the transport roller 64 (an example of a transport roller) is disposed in the reverse transport path 66. The transport roller 64 is rotatably supported by an arm 64A. The arm 64A is supported by a shaft 27. That is, the shaft 27 supports the feed roller 25 and the arm 64. The transport roller 64 faces the focus roller 59. The transport roller 64 is driven by a transport motor 102 (see FIG. 4). The transport roller 64 can rotate in the forward direction to transport the paper 12 in the reverse direction 22 regardless of whether the forward rotation force or the reverse rotation force of the transport motor 102 is transmitted to the transport roller 64.

[0034] [Flap 67] As shown in FIG. 2, the flap 67 is located at a connection position between the straight conveying path of the conveying path 65 and the reverse conveying path 66. The flap 67 is a guide plate that can rotate around the axis of the reverse roller 68. The flap 67 rotates between a first position shown by a solid line in FIG. 2 and a second position shown by a dashed line. The flap 67 in the first position divides the straight conveying path of the conveying path 65 and guides the paper 12 conveyed in the conveying direction 16 to the discharge tray 21. The flap 67 in the second position divides the reverse conveying path 66 and guides the paper 12 conveyed in the reverse direction 22, which is the opposite direction to the conveying direction 16 and faces backward on the reverse conveying path 66, to the conveying roller 64. The flap 67 is in the first position when the reverse roller 68 conveys the paper 12 in the feeding direction 16, and is in the second position when the reverse roller 68 conveys the paper 12 in the reverse direction 22.

[0035] [Record 24] As shown in FIG. 2, the recording unit 24 is disposed between the transport roller unit 54 and the discharge roller unit 55 in the transport direction 16. The recording unit 24 faces the platen 42 in the up-down direction 7. The recording unit 24 includes a carriage 23 and a recording head 39. As shown in FIG. 3, an ink tube 32 and a flexible flat cable 33 extend from the carriage 23. The ink tube 32 supplies ink from the ink cartridge to the recording head 39. The flexible flat cable 33 electrically connects a control board on which the control unit 130 is mounted to the recording head 39.

[0036] As shown in Fig. 3, the carriage 23 is supported by guide rails 43, 44 that extend in the left-right direction 9 at positions spaced apart in the front-rear direction 8. The carriage 23 is connected to a known belt mechanism provided on the guide rail 44. This belt mechanism is driven by a carriage motor 103 (see Fig. 4). Due to the collective motion of the belt mechanism, the carriage 23 reciprocates in the main scanning direction along the left-right direction 9.

[0037] 2, the recording head 39 is mounted on the carriage 23. A plurality of nozzles 40 are formed on the bottom surface of the recording head 39. The recording head 39 ejects ink as minute ink droplets from the nozzles 40. As the carriage 23 moves, the recording head 39 ejects ink droplets onto the paper 12 supported by a platen 42. In this way, an image is recorded on the paper 12.

[0038] When recording an image on the paper 12, the carriage 23 reciprocates in the left-right direction 9 within a range in which the recording head 39 can eject ink droplets onto the paper 12. Specifically, the carriage 23 reciprocates within a range in which at least a portion of the recording head 39 is directly above the transport path 65 and the platen 42. Hereinafter, the range in which the carriage 23 reciprocates when recording an image is referred to as the printing area.

[0039] The carriage 23 can move to the right of the printing area, outside the printing area. The home position of the carriage 23 is located to the right of the printing area. The carriage 23 is controlled to be located in the home position when an operation such as image recording is not being performed. The home position may be located to the left of the printing area.

[0040] [Platen 42] 2, the platen 42 is disposed between the transport roller unit 54 and the discharge roller unit 55 in the linear transport path of the transport path 65. The platen 42 faces the recording unit 24 in the up-down direction 7. The platen 42 supports the paper 12 from below.

[0041] [Maintenance mechanism 110 and cap 114] 5 performs maintenance on the recording head 39. In this embodiment, the maintenance mechanism 110 sucks ink from the nozzles 40 of the recording head 39 and sends the sucked ink through a tube 121 to a waste ink tank 120.

[0042] The maintenance mechanism 110 is disposed directly below the carriage 23 in the basic position. Note that in Fig. 5, the waste ink tank 120 is illustrated diagrammatically to show that the maintenance mechanism 110 and the waste ink tank 120 are connected by a tube 121, but this does not show the positional relationship between the waste ink tank 120 and other components.

[0043] The maintenance mechanism 110 includes a movable part 111, a cam mechanism 112 that moves the movable part 111 in the vertical direction 7, a tube 121 through which ink flows, and a pump 113 that sucks the ink.

[0044] The movable part 111 is provided with a cap 114 made of a rubber material. The cap 114 is provided at a position facing the carriage 23 in the home position in the up-down direction 7. The cam mechanism 112 is driven by the feed motor 101 (see FIG. 4) and moves the movable part 111 in the up-down direction 7. By transmitting a driving force from the feed motor 101, the cap 114 moves to a separated position separated from the nozzles 40 of the recording head 39 mounted on the carriage 23 in the home position, and a covering position where the cap 114 comes into contact with the lower surface of the recording head 39 and covers the nozzles 40.

[0045] One end of a tube 121 is connected to the cap 114. The tube 121 is a flexible resin tube. The other end of the tube 121 is connected to a waste ink tank 120.

[0046] In this embodiment, the pump 113 is a rotary tube pump. The pump 113 has a casing with an inner wall surface and a rolling roller that rolls along the inner wall surface. A tube 121 is disposed between the rolling roller and the inner wall surface. The rolling roller is driven by a conveying motor 102 (see FIG. 4). When the rolling roller is driven, the tube 121 is rotated, ink in the nozzle 40 is sucked into the tube 121, and the ink in the tube 121 is pushed out from the upstream side (cap 114) to the downstream side (waste ink tank 120).

[0047] The waste ink tank 120 is a roughly rectangular box shape having an internal space. An ink absorber (not shown) is accommodated in the internal space. The waste ink tank 120 can accommodate the ink sucked from the nozzles 40 by the ink absorber absorbing the ink.

[0048] [Drive force transmission mechanism 70] The driving force transmission mechanism 70 is configured by combining all or part of gears, pulleys, an endless loop belt, etc. As shown in Fig. 6 to Fig. 11, the driving force transmission mechanism 70 includes a first transmission part 181, a second transmission part 182, a third transmission part 183, a fourth transmission part 184, a fifth transmission part 185, a sixth transmission part 186, a seventh transmission part 187, and a slide mechanism 170. Note that the specific configuration of the driving force transmission mechanism 70 (e.g., the number of gears, etc.) is not limited to that described below.

[0049] The first transmission unit 181 transmits the driving force of the conveying motor 102 to the conveying roller 60 and the slide mechanism 170. The second transmission unit 182 transmits the driving force of the feed motor 101 to the shaft 27. The third transmission unit 183 transmits the driving force of the conveying motor 102 from the conveying roller 60 to the discharge roller 62 and the reverse roller 68. The fourth transmission unit 184 transmits the driving force of the conveying motor 102 from the slide mechanism 170 to the pump 113. The fifth transmission unit 185 transmits the driving force of the conveying motor 102 from the slide mechanism 170 to the shaft 27. The sixth transmission unit 186 transmits the rotation of the shaft 27 to the feed roller 25. The seventh transmission unit 187 transmits the rotation of the shaft 27 to the conveying roller 64. The slide mechanism 170 switches the transmission destination of the driving force of the conveying motor 102. The first transmission part 181, a part of the fourth transmission part 184, and the slide mechanism 170 are an example of a first drive transmission mechanism.

[0050] [First transmission part 181] 6 and 8, the first transmission unit 181 includes a pulley 71 that rotates integrally with the shaft of the conveying motor 102, a pulley 72 that rotates integrally with the shaft 60A of the conveying roller 60, and an endless annular belt 73 that is stretched around the pulleys 71 and 72. As a result, the conveying roller 60 rotates in the forward direction by the forward rotation force of the conveying motor 102 being transmitted thereto, and rotates in the reverse direction by the reverse rotation force of the conveying motor 102 being transmitted thereto. The rotation of the conveying roller 60 rotates a roller gear 180 of the slide mechanism 170 that rotates integrally with the shaft 60A of the conveying roller 60. As described above, the first transmission unit 181 transmits the driving force of the conveying motor 102 to the conveying roller 60 and the slide mechanism 170.

[0051] [Second transmission part 182] As shown in Figs. 7 and 11, the second transmission unit 182 includes a gear 74 that rotates integrally with the shaft of the feed motor 101, gears 79 to 81, a planetary gear 82 that meshes with the gear 81 and rotates around the gear 81, and a gear 83 that meshes with the planetary gear 82. The shafts of the gears that constitute the second transmission unit 182 are supported by the side frame 176. The gear 83 meshes with a gear 84 that rotates integrally with the shaft 27. This allows the feed motor 101 to apply a driving force to the shaft 27. In addition, the planetary gear 82 meshes with the gear 83 when the feed motor 101 rotates forward, and is separated from the gear 83 when the feed motor 101 rotates reversely. Therefore, the second transmission part 182 transmits the forward rotation of the feed motor 101 to the shaft 27, and when the feed motor 101 rotates in the reverse direction, the second transmission part 182 releases the drive transmission to the shaft 27, allowing the shaft 27 to rotate freely.

[0052] [Third Transmission Section 183] 6, the third transmission part 183 includes gears 75 and 76 that mesh with each other, pulleys 77 and 78, and an endless circular belt 81. The third drive transmission part 183 also includes a pulley 85 that rotates integrally with the pulley 78, pulleys 86 and 87 that rotate integrally with the pulley 78, and endless circular belts 88 and 89.

[0053] The gear 75 meshes with the gear 76 and rotates integrally with the shaft 60A of the conveying roller 60. The gear 76 and the pulley 77 rotate integrally on the same shaft. The pulley 78 is attached to the shaft 62A of the discharge roller 62. The belt 81 is stretched between the pulleys 77 and 78. The pulley 87 is attached to the shaft 68A of the reverse roller 68. The belt 88 is stretched between the pulleys 85 and 86. The belt 89 is stretched between the pulleys 86 and 87. As a result, the discharge roller 62 and the reverse roller 68 rotate forward by the forward rotation force of the conveying motor 102 being transmitted thereto, and rotate reversely by the reverse rotation force of the conveying motor 102 being transmitted thereto. In this way, the third transmission unit 183 transmits the driving force of the conveying motor 102 from the conveying roller 60 to the discharge roller 62 and the reverse roller 68.

[0054] [Fourth Transmission Part 184] 6, the fourth transmission unit 184 includes a gear 157 that can mesh with the slide gear 160 of the slide mechanism 170, and a gear 158 that meshes with the gear 157 and rotates integrally with the shaft of the rolling roller of the pump 113. As a result, the pump 113 is driven by the driving force transmitted from the slide gear 160. In this way, the fourth transmission unit 184 transmits the driving force (reverse rotation force in this embodiment) of the conveying motor 102 from the slide mechanism 170 to the pump 113.

[0055] [5th ​​Transmission Section 185] As shown in FIG. 6, FIG. 10, and FIG. 11, the fifth transmission unit 185 includes a gear 90 (an example of a third transmission gear) meshed with the slide gear 160, a gear 91 (an example of a first transmission gear), a sun gear 92, planetary gears 93 and 94 (an example of a first planetary gear, a second planetary gear, and a counterweight), and gears 95 to 100. The shafts of the gears constituting the fifth transmission unit 185 are supported by the side frame 176. More specifically, the gear 91 meshes with the gear 90. The sun gear 92 meshes with the planetary gears 93 and 94, respectively. The planetary gear 93 can mesh with a gear 96 (an example of a second transmission gear). The planetary gear 94 can mesh with the gear 95. The gears 95 to 100 mesh in series. The gear 100 meshes with the gear 83. The fifth transmission portion 185 is an example of a third drive transmission mechanism.

[0056] The sun gear 92 is supported by the shaft 91A of the gear 91. The arm 188 is rotatably supported by the shaft 91A of the gear 91 and extends in two directions from the shaft 91A. The planetary gears 93 and 94 are rotatably supported at the ends of the arm 188 extending in two directions from the shaft 91A. As a result, when the sun gear 92 rotates, the planetary gears 93 and 94 can revolve around the sun gear 92. As shown in FIGS. 10 and 11, a leaf spring 189 (an example of a counterweight) is provided at the end of the arm 188 that supports the planetary gear 94. The leaf spring 189 holds the planetary gear 94 from the outside of the arm 188 and biases the arm 188 inward so that the arm 188 presses against the side of the planetary gear 94. Due to the bias of the leaf spring 189, the sliding frictional force generated against the arm 188 when the planetary gear 94 rotates is greater than the sliding frictional force generated against the arm 188 when the planetary gear 93 rotates.

[0057] The total weight of the planetary gear 94 and the leaf spring 189 is greater than the weight of the planetary gear 93. When the planetary gear 93 is engaged with the gear 96, the planetary gear 94 is located on the opposite side to the planetary gear 93 with respect to an imaginary line that includes the center of the shaft 91A and runs along the up-down direction 7. In Figs. 10 and 11, the planetary gear 93 is located in front of the imaginary line, and the planetary gear 94 and the leaf spring 189 are located behind the imaginary line. Therefore, when the planetary gear 93 is engaged with the gear 96, the planetary gear 94 and the leaf spring 189 function as a counterweight that applies a load to move the planetary gear 93 in a direction away from the gear 96.

[0058] Depending on the rotation direction of the sun gear 92, the planetary gear 93 meshes with the gear 96 or the planetary gear 94 meshes with the gear 95. In this embodiment, when the sun gear 92 rotates counterclockwise in FIG. 11, the planetary gear 93 meshes with the gear 96. When the sun gear 92 rotates clockwise, the planetary gear 94 meshes with the gear 95. The gear 96 rotates clockwise whether the sun gear 92 rotates clockwise or counterclockwise. Therefore, the rotation direction of the gears 96 to 100 is constant regardless of the rotation direction of the sun gear 92. In this way, the fifth transmission unit 185 transmits the driving force of the conveying motor 102 from the slide mechanism 170 to the shaft 27.

[0059] [6th Transmission Section 186] 7 and 9, the sixth transmission unit 186 includes a sun gear 151 that rotates integrally with the shaft 27, a planetary gear 152 that is supported by an arm 152A that rotates around the axis of the sun gear 151 and meshes with the sun gear 151, a gear train 153, and a gear 154. The gear train 153 meshes with the gear 154 that rotates integrally with the feed roller 25.

[0060] Depending on the rotation direction of the sun gear 151, the planetary gear 152 meshes with the gear train 153 or separates without meshing. In this embodiment, when the sun gear 151 rotates clockwise in FIG. 9, the planetary gear 152 meshes with the gear train 153. When the sun gear 151 rotates counterclockwise, the planetary gear 152 separates from the gear train 153. When the feed motor 101 rotates forward, the shaft 27 rotates clockwise via the second transmission unit 182, and the sun gear 151 also rotates clockwise. Therefore, when the feed motor 101 rotates forward, the feed roller 25 rotates so as to feed the paper 12 in the feed direction 16. When the feed motor 101 rotates reversely, the drive transmission is released in the second drive transmission unit 182, and the reverse rotation of the feed motor 101 is not transmitted to the shaft 27. In this manner, the sixth transmission portion 186 transmits the rotation of the shaft 27 to the feed roller 25.

[0061] [7th Transmission Section 187] 7 and 9, the seventh transmission portion 187 includes a gear 155 that rotates integrally with the shaft 27, and a gear 156 that rotates integrally with the conveying roller 64. The gears 155 and 156 are in mesh with each other.

[0062] When the conveying motor 102 rotates forward or backward with the slide gear 160 meshing with the gear 90, the shaft 27 rotates counterclockwise and the gear 155 also rotates counterclockwise via the fifth transmission unit 185. Therefore, when the conveying motor 102 rotates with the slide gear 160 meshing with the gear 90, the conveying roller 64 rotates so as to convey the paper 12 in the reverse direction 22. When the shaft 27 rotates counterclockwise, the planetary gear 152 moves away from the gear train 153 in the sixth transmission unit 186, so that the rotation of the shaft 27 is not transmitted to the feed roller 25. In this way, the seventh transmission unit 187 transmits the rotation of the shaft 27 to the conveying roller 64.

[0063] [Slide mechanism 170] The slide mechanism 170 is a mechanism for moving the slide gear 160 in the left-right direction 9. The slide mechanism 170 includes a carriage 23 (see FIG. 3), a lever member 175 (see FIG. 12), a first coil spring 168 (an example of a biasing member, see FIG. 12), a second coil spring 169 (see FIG. 12), and a holding portion 173 (see FIG. 13). Note that the first coil spring 168 and the second coil spring 169 are omitted from illustrations other than FIG. 12.

[0064] 10 and 12, the lever member 175 is disposed on the right side of the slide gear 160 and in contact with the slide gear 160. In other words, the lever member 175 is disposed to the right of the slide gear 160.

[0065] The lever member 175 includes a main body 175A in contact with the slide gear 160, and a protruding portion 175B protruding upward from the main body 175A. A support shaft 174 is inserted through the main body 175A. This allows the main body 175A to be supported by the support shaft 174 so as to be movable and rotatable in the left-right direction 9. The protruding portion 175B extends to a movement region of the carriage 23 outside the printing region. This allows the protruding portion 175B to come into contact with the carriage 23 moving rightward and be pushed rightward.

[0066] 12, the first coil spring 168 is disposed to the right of the lever member 175. A support shaft 174 is inserted through the first coil spring 168. One end of the first coil spring 168 abuts against the lever member 175. The other end of the first coil spring 168 abuts against a frame (not shown) of the printer unit 11 or the like. This enables the first coil spring 168 to urge the lever member 175 leftward.

[0067] 12, the second coil spring 169 is disposed to the left of the second slide gear 160B. A support shaft 174 is inserted through the second coil spring 169. One end of the second coil spring 169 abuts against the slide gear 160. The other end of the second coil spring 169 abuts against a side frame 176 of the printer unit 11. This allows the second coil spring 169 to urge the slide gear rightward.

[0068] The biasing force of the second coil spring 169 is smaller than the biasing force of the first coil spring 168. As a result, the slide gear 160 and the lever member 175 are biased leftward.

[0069] 13, holding portion 173 is provided above main body portion 175A of lever member 175. An opening 177 is formed in holding portion 173. Protrusion 175B of lever member 175 is inserted into opening 177 from below toward above. A first stopper 178, a second stopper 179 provided to the right of first stopper 178, and an inclined surface 172 provided to the right of second stopper 179 are formed on the edge of opening 177.

[0070] 12 and 15, the first stopper 178 comes into contact with the protrusion 175B when the slide gear 160 is in the left position LP. This restricts the lever member 175 from moving leftward from the left position LP due to the biasing force of the first coil spring 168. On the other hand, the first stopper 178 does not restrict the lever member 175 from moving rightward. In the left position LP, the slide gear 160 does not mesh with other gears. Therefore, when the slide gear 160 is in the left position LP, no drive is transmitted from the slide mechanism 170 to the conveying roller 64 and the pump 113.

[0071] 12 and 16, the second stopper 179 engages with the protrusion 175B when the slide gear 160 is located at the first central position MP1. This restricts the lever member 175 from moving leftward from the first central position MP1 by the biasing force of the first coil spring 168. On the other hand, the second stopper 179 does not restrict the lever member 175 from moving rightward.

[0072] As shown in FIG. 12 and FIG. 18, when the slide gear 160 is held at the left position LP (when the protrusion 175B is engaged with the first stopper 178), the protrusion 175B comes into contact with and is pushed by the carriage 23 moving to the right, and the lever member 175 moves to the right against the biasing force of the first coil spring 168. At this time, the second slide gear 160B, which is biased to the right by the second coil spring 169, moves to the right along with the movement of the lever member 175. The slide gear 160 moves to the right by being pushed by the moving second slide gear 160B. The protrusion 175B engages with the second stopper 179, and the slide gear 160 is held at the first center position MP1 (an example of the first slide position). At the first center position MP1, the slide gear 160 meshes with the gear 90. Therefore, when the slide gear 160 is in the first central position MP1, the driving force is transmitted from the slide mechanism 170 to the transport roller 64.

[0073] When the slide gear 160 is held at the first central position MP1 (when the protrusion 175B is engaged with the second stopper 179), and the protrusion 175B comes into contact with and is pushed by the carriage 23 moving to the right, the lever member 175 moves to the right against the biasing force of the first coil spring 168. At this time, the second slide gear 160B biased rightward by the second coil spring 169 moves to the right in conjunction with the movement of the lever member 175. The slide gear 160 moves to the right, pushed by the moving second slide gear 160B.

[0074] When the protruding portion 175B moves to the right end of the inclined surface 172, the lever member 175 rotates so that the protruding portion 175B moves rearward. On the other hand, when the protruding portion 175B is located leftward of the right end of the inclined surface 172, the lever member 175 is held in a state in which the protruding portion 175B is located forward.

[0075] In a state where the protruding portion 175B is located to the right of the second stopper 179, the carriage 23 maintains contact with the protruding portion 175B, and the slide gear 160 is held in the right position RP. The position of the carriage 23 at this time is the home position. In other words, the slide gear 160 is held in the right position RP against the biasing force of the first coil spring 168, as the carriage 23 in the home position abuts against the protruding portion 175B.

[0076] In addition, in a state where the protruding portion 175B is located to the right of the second stopper 179 and to the left of the right position RP, the carriage 23 maintains contact with the protruding portion 175B, and the slide gear 160 is held at the second center position MP2 (an example of the second slide position) as shown in FIG. 12 and FIG. 16. When the carriage 23 moves leftward and separates from the protruding portion 175B in a state where the slide gear 160 is held at the second center position MP2, the lever member 175 moves leftward due to the biasing force of the first coil spring 168. Then, the protruding portion 175B of the lever member 175 engages with the second stopper 179. As a result, the slide gear 160 moves from the second center position MP2 to the first center position MP1. In the second center position MP2, the slide gear 160 does not mesh with other gears. Therefore, when the slide gear 160 is in the second central position MP2, the driving force is not transmitted from the slide mechanism 170 to the conveying roller 64 and the pump 113.

[0077] When the carriage 23 moves leftward and separates from the protruding portion 175B while the slide gear 160 is held at the right position RP, the lever member 175 moves leftward by the biasing force of the first coil spring 168. At this time, as described above, the protruding portion 175B has moved rearward, so it does not engage with the second stopper 179 and moves leftward beyond the second stopper 179. As a result, the lever member 175 moves leftward until the protruding portion 175B abuts against the first stopper 178. At this time, the slide gear 160 is pushed by the lever member 175 and moves from the right position RP to the left position LP. In other words, the slide gear 160 is moved to the left position LP by the biasing force of the first coil spring 168 as the carriage 23 separates from the protruding portion 175B. At the right position RP, the slide gear 160 meshes with the gear 157. Therefore, when the slide gear 160 is in the right position RP, the driving force is transmitted from the slide mechanism 170 to the pump 113 .

[0078] When lever member 175 moves leftward, protrusion 175B moves along inclined surface 171 formed in the vicinity of first stopper 178 at the edge of opening 177. This causes lever member 175 to rotate such that protrusion 175B moves forward.

[0079] [Clutch mechanism 190] 14, the clutch mechanism 190 is composed of a key 191 provided on the shaft 91A of the gear 91 and a key groove 192 provided in a shaft hole 92A of the sun gear 92. The clutch mechanism 190 is an example of a second drive transmission mechanism.

[0080] The keys 191 protrude in two radially outward directions from the shaft 91A. The two keys 191 are out of phase with each other by 180° with respect to the axis 105 of the shaft 91A. The outer circumferential surface of the shaft 91A between the two keys is a circumferential surface. The two keys 191 have the same shape.

[0081] The key grooves 192 are located at two locations circumferentially of the shaft hole 92A of the sun gear 92. The two key grooves 192 are out of phase with each other by 180° with respect to the axis 105 of the shaft hole 92A. The surface between the key grooves 192 in the shaft hole 92A is a circumferential surface. The two key grooves 192 have the same shape. When the shaft 91A is inserted into the shaft hole 92A, the axis of the shaft 91A and the axis of the shaft hole 92A coincide with each other, so both axes will be referred to as the axis 105.

[0082] One end of the key groove 192 in the circumferential direction 104 is defined by a side surface 192 (an example of a first surface). The other end of the key groove 192 in the circumferential direction 104 is defined by a side surface 193 (an example of a second surface). The length in the circumferential direction 104 between the side surfaces 192, 193 is longer than the length in the circumferential direction 104 of the key 191.

[0083] With the shaft 91A inserted through the shaft hole 92A, the two keys 191 are inserted into the two key grooves 192, respectively. With the key 191 not in contact with the side surface 192, the shaft 91A to which a positive rotational force is transmitted from the conveying motor 102 rotates counterclockwise in FIG. 14. This causes the key 191 to approach the side surface 192. When the key 191 comes into contact with the side surface 192 and presses against it, the sun gear 92 rotates counterclockwise together with the shaft 91A.

[0084] On the other hand, when the key 191 is not in contact with the side surface 193, the shaft 91A to which the reverse rotational force is transmitted from the carry motor 102 rotates clockwise in Fig. 14. As a result, the key 191 approaches the side surface 193. Then, when the key 191 comes into contact with the side surface 193 and presses the side surface 193, the sun gear 92 rotates clockwise together with the shaft 91A.

[0085] Furthermore, when the drive of the conveying motor 101 is reversed, the key 191 abutting against the side surface 192 moves away from the side surface 192 and approaches the side surface 193, and then abuts against the side surface 193. Furthermore, the key 191 abutting against the side surface 193 moves away from the side surface 193 and approaches the side surface 192, and then abuts against the side surface 192. When the key 191 is not abutting against either the side surface 192 or 193, the sun gear 92 does not rotate even if the shaft 91A rotates. In other words, the shaft 91A rotates idly relative to the sun gear 92.

[0086] [Control unit 130] 4, the control unit 130 includes a CPU 131, a ROM 132, a RAM 133, an EEPROM 134, and an ASIC 135, which are connected by an internal bus 137. The ROM 132 stores programs and the like for the CPU 131 to control various operations. The RAM 133 is used as a storage area for temporarily recording data, signals, and the like used when the CPU 131 executes the programs, or as a working area for data processing. The EEPROM 134 stores settings, flags, and the like that should be retained even after the power is turned off.

[0087] The ASIC 135 is connected to the feed motor 101, the conveying motor 102, the carriage motor 103, and the like. The ASIC 135 generates a drive signal for rotating each motor, and controls each motor based on the drive signal. Each motor rotates forward or backward according to the drive signal from the ASIC 135. For example, the control unit 130 controls the drive of the feed motor 101 to rotate the feed roller 25. The control unit 130 also controls the drive of the conveying motor 102 to rotate each of the rollers 60, 62, 64, and 68 and drive the pump 113. The control unit 130 also controls the drive of the carriage motor 103 to reciprocate the carriage 23. The control unit 130 also controls the recording head 39 to eject ink from the nozzles 40. As described above, the control unit 130 controls the conveying motor 102 and the slide mechanism 170.

[0088] [Double-sided recording processing] The process of double-sided recording by the printer unit 11 will be described below with reference to Fig. 19. Each process is executed by the CPU 131 of the control unit 130. Note that each process may be executed by the CPU 131 reading out a program stored in the ROM 132, or may be realized by a hardware circuit mounted on the control unit 130.

[0089] When the printer unit 11 is not operating, the carriage 23 is located at the basic position, so that the carriage 23 holds the protruding portion 175B of the lever member 175 at the right position RP.

[0090] When a double-sided recording instruction is input through the operation panel 17, or when a double-sided recording instruction is received from an external information device (S10: Yes), the control unit 130 executes a slide process (S11). The slide process is a process in which the carriage motor 103 is driven to move the carriage 23 leftward from the base position to a position near the printing area. In the slide process, the lever member 175 moves leftward together with the movement of the carriage 23, and the slide gear 160 moves from the right position RP to the left position LP.

[0091] When the slide process is completed, the control unit 130 executes the feeding process (S12). In the feeding process, the control unit 130 rotates the feeding motor 101 in the forward direction. As a result, the rotation of the shaft 27 is transmitted to the feeding roller 25, which rotates, and the paper 12 loaded on the feeding tray 20 is fed to the conveying path 65. When the feeding motor 101 rotates in the forward direction, the gear 83 of the second transmission unit 182 rotates. Therefore, the gear 100 of the fifth transmission unit 185 meshing with the gear 83 also rotates, but since the slide gear 160 is in the left position LP, the rotation of the gear 100 is not transmitted to the slide gear 160. Therefore, the conveying motor 102 can be rotated while the feeding motor 101 is rotated in the forward direction. The front end of the paper 12 loaded on the paper feed tray 20 reaches the conveying roller unit 54 by the feeding process.

[0092] When the feeding process is completed, the control unit 130 rotates the feeding motor 101 slightly in the reverse direction. The reverse rotation of the feeding motor 101 separates the planetary gear 82 of the second transmission unit 182 from the gear 83. The control unit 130 also moves the slide gear 160 from the left position LP to the first central position MP1 (S13). In detail, the control unit 130 drives the carriage motor 103 to move the carriage 23 to the right. Pushed by the carriage 23, the lever member 175 also moves to the right. The slide gear 160 is also biased by the second coil spring 169 to move from the left position LP to the first central position MP1.

[0093] When the slide gear 160 moves, the control unit 130 causes the conveying motor 102 to repeatedly rotate slightly in the forward and reverse directions several times. Due to such slight rotations of the conveying motor 102, the slide gear 160 also repeatedly rotates slightly in the forward and reverse directions. Due to the slight rotations of the slide gear 160, the phases of the teeth of the slide gear 160 and the teeth of the gear 90 match, and the slide gear 160 meshes with the gear 90.

[0094] Next, the control unit 130 executes the conveying process (S14). In the conveying process, the control unit 130 rotates the conveying motor 102 in the forward direction. This causes the conveying roller 60 to rotate in the forward direction, and the sheet is sandwiched between the conveying roller unit 54 and conveyed in the conveying direction 16 directly below the recording unit 24. In addition, the forward rotation of the conveying motor 102 also causes the discharge roller 62 and the reversing roller 68 to rotate in the forward direction.

[0095] Next, the control unit 130 executes a first side printing process (S15). In the first side printing process, the control unit 130 alternately executes a recording operation in which ink droplets are ejected from the nozzles 40 of the recording head 39 while reciprocating the carriage 23 in the printing area, and a transport operation in which the transport motor 102 is rotated forward a predetermined amount to transport the sheet by an amount equivalent to a line feed. As a result, an image is recorded on the first side of the paper 12 that faces the recording head 39.

[0096] After printing on the first side of the paper 12 is completed, the control unit 130 rotates the conveying motor 102 in the forward direction until the rear end of the paper 12 reaches immediately upstream of the reversing roller 68 in the feeding direction 16 (S16). As a result, the rear end of the paper 12 reaches the position where the conveying path 65 and the reversing conveying path 66 branch off.

[0097] Next, the control unit 130 rotates the conveying motor 102 in the reverse direction (S17). When the conveying motor 102 rotates in the reverse direction, the reversing roller 68 rotates in the reverse direction, and the paper 12 is conveyed in the reverse direction 22 and enters the reversing conveying path 66. The conveying roller 64 rotates, and the paper 12 is conveyed in the reverse direction 22 in the reversing conveying path 66. Furthermore, the paper 12 that re-enters the curved path of the conveying path 65 from the reversing conveying path 66 is in a state in which the front end and rear end in the first side printing process are reversed, that is, the first side and the second side are reversed. The paper 12 with the first side and the second side reversed reaches the conveying roller unit 54. The second side of the paper 12 is the side opposite to the first side. Furthermore, when the feeding process is completed, the planetary gear 82 is separated from the gear 83 in the second transmission section 182, so even if the shaft 27 is rotated by the conveying motor 102, the rotation of the shaft 27 is not transmitted to the feeding motor 101.

[0098] Next, the control unit 130 executes a second side printing process (S18). In the second side printing process, the control unit 130 alternately executes a recording operation in which ink droplets are ejected from the nozzles 40 of the recording head 39 while reciprocating the carriage 23 in the printing area, and a transport operation in which the transport motor 102 is rotated forward a predetermined amount to transport the sheet by an amount equivalent to a line feed. As a result, an image is recorded on the second side of the paper 12 that faces the recording head 39.

[0099] After printing on the second side of the paper 12 is completed, the control unit 130 executes the discharge process (S19). In the discharge process, the control unit 130 rotates the conveying motor 102 in the forward direction. This causes the discharge rollers 62 and the reverse rollers 68 to rotate in the forward direction, and the sheet is sandwiched between the discharge roller unit 55 and the reverse roller unit 56 and conveyed in the conveying direction 16. As a result, the sheet is discharged to the discharge tray 21.

[0100] Next, the control unit 130 determines (S20) whether there is printing to be performed on the next sheet 12. If there is no printing to be performed on the next sheet 12 (S20: No), the control unit 130 ends the double-sided recording process.

[0101] If there is printing to be performed on the next paper 12 (S20: Yes), the control unit 130 moves the slide gear 160 from the first center position MP1 to the second center position MP2 (S21). In detail, the control unit 130 drives the carriage motor 103 to move the carriage 23 to the right. Pushed by the carriage 23, the lever member 175 also moves to the right. Also, the slide gear 160 is biased by the second coil spring 169 to move from the first center position MP1 to the second center position MP2.

[0102] When the slide gear 160 moves, the control unit 130 causes the conveying motor 102 to rotate forward and backward slightly several times (an example of a rotation process). Such a slight rotation of the conveying motor 102 causes the slide gear 160 to rotate forward and backward slightly. The slight rotation of the slide gear 160 is transmitted to the gear 91 of the fifth transmission unit 185. When the conveying motor 102 rotates forward and backward from a state in which the planetary gear 93 is engaged with the gear 96, the clutch mechanism 190 allows the sun gear 92 to rotate freely with respect to the shaft 91A of the gear 91. The planetary gear 93, which is receiving surface pressure from the planetary gear 93, the gears 96 to 100, and the gear 83, moves in a direction away from the gear 96. As a result, the surface pressure from the planetary gear 93, the gears 96 to 100, and the gear 83 disappears. In the movement of the planetary gear 93, the planetary gear 94 and the leaf spring 189 function as counterweights, and the planetary gear 93 also moves in a direction away from the gear 96 due to the weight of the planetary gear 94 and the leaf spring 189. As the planetary gear 93 moves, the sun gear 92 rotates idly relative to the shaft 91A, thereby reducing the surface pressure of the gear 90 meshing with the slide gear 160 at the first central position MP1. In addition, the planetary gear 94, which has a relatively large sliding friction, moves together with the sun gear 92 due to the idling of the sun gear 92, so that the planetary gear 93 further moves in a direction away from the gear 96. Therefore, when the conveying motor 102 is slightly rotated in the reverse direction, the surface pressure between the slide gear 160 and the gear 90 at the first central position MP1 also decreases. As a result, the slide gear 160 is biased by the second coil spring 169 and moves smoothly from the first central position MP1 to the second central position MP2.

[0103] Next, the control unit 130 executes the feeding process (S22). In the feeding process, the control unit 130 rotates the feeding motor 101 in the forward direction. As a result, the rotation of the shaft 27 is transmitted to the feeding roller 25, which rotates, and the paper 12 loaded on the feeding tray 20 is fed to the conveying path 65. When the feeding motor 101 rotates in the forward direction, the gear 83 of the second transmission unit 182 rotates. Therefore, the gear 100 of the fifth transmission unit 185 meshing with the gear 83 also rotates, but since the slide gear 160 is at the second center position MP2, the rotation of the gear 100 is not transmitted to the slide gear 160. Therefore, the conveying motor 102 can be rotated while rotating the feeding motor 101 in the forward direction. The front end of the paper 12 loaded on the paper feeding tray 20 reaches the conveying roller unit 54 by the feeding process.

[0104] When the feeding process is completed, the control unit 130 rotates the feeding motor 101 slightly in the reverse direction. The reverse rotation of the feeding motor 101 separates the planetary gear 82 of the second transmission unit 182 from the gear 83. The control unit 130 also moves the slide gear 160 from the second center position MP2 to the first center position MP1 (S23). In detail, the control unit 130 drives the carriage motor 103 to move the carriage 23 to the left. When the carriage 23 separates from the lever member 175 to the right, the slide gear 160 is biased by the second coil spring 169 and attempts to move from the second center position MP2 to the first center position MP1.

[0105] When the slide gear 160 moves, the control unit 130 causes the conveying motor 102 to repeatedly rotate slightly in the forward and reverse directions several times. Due to such slight rotations of the conveying motor 102, the slide gear 160 also repeatedly rotates slightly in the forward and reverse directions. Due to the slight rotations of the slide gear 160, the phases of the teeth of the slide gear 160 and the teeth of the gear 90 match, and the slide gear 160 meshes with the gear 90.

[0106] Then, the control unit 130 executes the process from the conveying process (S14) to the discharging process (S19) in the same manner as described above. If there is further printing on the next sheet 12 (S20: Yes), the control unit 130 executes the process of S21, and if there is no further printing on the next sheet 12 (S20: No), ends the double-sided recording process.

[0107] [Effects of this embodiment] According to this embodiment, when the forward rotation of the conveying motor 102 is transmitted to the gear 96 via the sun gear 92 and the planetary gear 93, the conveying motor 102 rotates slightly in the reverse direction, and the sun gear 92 becomes free to rotate with respect to the shaft 91A of the gear 91, and the planetary gear 93 moves in a direction away from the gear 96 due to the surface pressure from the gear 96. Surface pressure from the planetary gear 93, the gears 96 to 100, and the gear 83 disappears. In addition, the sun gear 92 rotates free with the movement of the planetary gear 93, and the surface pressure between the slide gear 160 and the gear 90 decreases. Therefore, the amount of reverse rotation of the conveying motor 102 is reduced in order to reduce the surface pressure between the slide gear 160 and the gear 90. In particular, the time required to move the slide gear 160 from the first central position MP1 to the second central position MP2 is shortened, and the time required for double-sided recording processing is shortened.

[0108] In addition, since the planetary gear 94 and the leaf spring 189 function as a counterweight, the planetary gear 93 tends to move in a direction away from the gear 96 .

[0109] [Variations] In the above embodiment, the clutch mechanism 190 transmits the drive force between the shaft 91A of the gear 91 and the sun gear 92, but the clutch mechanism 190 may be realized as a mechanism for transmitting the drive force in other ways. For example, the clutch mechanism 190 may be realized as a mechanism for transmitting the drive force between the gear 81 and the planetary gear 82 in the second transmission section 182. In this case, after the feeding process is completed, the planetary gear 82 moves away from the gear 81, so that the amount of reverse rotation of the feeding motor 101 is reduced.

[0110] In the above embodiment, the clutch mechanism 190 has the key 191 provided on the shaft 91A of the gear 91 and the key groove 192 provided on the shaft hole 92A of the sun gear 92, but the clutch mechanism 190 may be realized in another form. For example, the gear 91 may have a shaft hole having the key groove 192 without the shaft 91A, and the sun gear 92 may have a shaft having the key 191 without the shaft hole 92A. Also, the key and the key groove may not be provided on the shaft or the shaft hole. For example, the side of the gear 91 and the side of the sun gear 92 may face each other, and driving force may be transmitted between the gear 91 and the sun gear 92 by the key and the key groove provided on each side.

[0111] In the above embodiment, the planetary gear 94 and the leaf spring 189 are realized as a counterweight for the planetary gear 93. However, instead of the planetary gear 94 and the leaf spring 189, a weight may be provided on the arm 188 as a counterweight.

[0112] Furthermore, in the above embodiment, the lever member 175 is disposed to the right of the slide gear 160, but it may be disposed in another position.

[0113] In the above embodiment, the conveying device is mounted on the printer unit 11 that records an image on the paper 12, but the conveying device may be mounted on a device other than the printer unit 11. For example, the conveying device may be provided in the multifunction device 10 or the like, and may be mounted on a scanner that reads an image recorded on the paper 12. [Explanation of symbols]

[0114] 11 Printer section (transport device) 23... Carriage 39 Recording head 64...Transport roller 90··· gear (third transmission gear) 91··· gear (first transmission gear) 92...Solar Gear 93 Planetary gear (first planetary gear) 94 Planetary gear (second planetary gear, counterweight) 96··· gear (second transmission gear) 102...Transport motor (motor) 130... Control unit 160···Slide gear 168... First coil spring (urging member) 170 Slide mechanism (first drive transmission mechanism) 175 Lever member 181... First transmission section (first drive transmission mechanism) 184...Fourth transmission section (first drive transmission mechanism) 185... 5th transmission section (3rd drive transmission mechanism) 189 Leaf spring (counterweight) 190 Clutch mechanism (second drive transmission mechanism) 192...Side (first side) 193...Side (2nd side)

Claims

1. A motor; Sun gear and a first drive transmission mechanism having a first transmission gear and configured to transmit a driving force of the motor to the first transmission gear; a second drive transmission mechanism that transmits a drive force from the first transmission gear of the first drive transmission mechanism to the sun gear and has a range in which the first transmission gear can rotate idly relative to the sun gear; a planetary gear that is rotatably supported by a support arm that is rotatable around the axis of the sun gear and that meshes with the sun gear; a third drive transmission mechanism having a second transmission gear that is capable of engaging with and disengaging from the planetary gear and is capable of meshing with the planetary gear; a conveying roller that conveys a sheet by being rotated by a driving force applied from the third drive transmission mechanism, A conveying device in which the support arm is provided with a counterweight for the planetary gear.

2. The first drive transmission mechanism is a slide gear that is slidably supported on a support shaft along the axial direction and rotates by a driving force transmitted from the motor; a third transmission gear capable of meshing with the slide gear and transmitting a driving force to the first transmission gear; a slide mechanism for sliding the slide gear, 2. The conveying device according to claim 1, wherein the slide mechanism slides the slide gear between a first slide position in which the slide gear meshes with the third transmission gear and a second slide position in which the slide gear does not mesh with the third transmission gear.

3. A control unit for controlling the motor and the slide mechanism is further provided. The control unit is a rotation process of rotating the motor in a reverse direction in a state in which the slide gear and the third transmission gear are engaged with each other; 3. The transport device according to claim 2, further comprising: a slide process for controlling the slide mechanism to slide the slide gear after the rotation process is performed.

4. a print head that ejects ink from a nozzle toward a sheet transported by the transport roller, the print head further comprising a print area in which the print head can eject ink toward the sheet, and a carriage that can move to a basic position outside the print area; The slide mechanism is The carriage; a lever member having a protruding portion protruding into a movement area of ​​the carriage, the lever member moving the slide gear from the first slide position toward the second slide position by contacting the carriage; 4. The conveying device according to claim 3, further comprising: a biasing member for biasing the slide gear from the second slide position to the first slide position.

5. The second drive transmission mechanism is a key groove provided on one of the first transmission gear or the sun gear, the key groove having a first surface and a second surface spaced apart along a circumferential direction; a key that is provided on the other of the first transmission gear or the sun gear and is located between the first surface and the second surface in the circumferential direction, 5. The conveying device according to claim 1, wherein the circumferential length of the key is shorter than the circumferential length between the first surface and the second surface.

6. the planetary gear is a first planetary gear rotatably supported by the support arm, 2. The transport apparatus according to claim 1, wherein the counterweight is a second planetary gear rotatably supported on the support arm.

7. 2. The conveying device according to claim 1, wherein the counterweight is heavier than the planetary gear.

Images