JP5664110B2 - Roll paper transport apparatus, roll paper transport method, and image recording apparatus - Google Patents

Description

  The present invention relates to a roll paper transport apparatus, a roll paper transport method, and an image recording apparatus.

  2. Description of the Related Art A printing apparatus including a guide device (unit) that rotates a frame including a pair of rollers arranged in the conveyance direction of roll paper around a rotation axis by driving a motor is known (for example, Patent Documents). 1).

JP 2009-73590 A

  In such a printing apparatus, when the unit is arranged inside, there are cases where the unit cannot be stored compactly as its thickness increases.

  The present invention has been made in view of such circumstances, and an object thereof is to reduce the thickness of the entire unit.

The main invention for solving the above problems is:
A roll paper is conveyed along the conveyance direction, and a first roller and a second roller arranged along the conveyance direction;
A base member that rotatably supports the first roller and the second roller around each central axis;
A rotation shaft that rotatably supports the base member along a normal direction of a virtual plane including the central axis of each of the first roller and the second roller;
A cam follower provided on the base member and protruding in the normal direction;
An eccentric cam that rotates around a central axis along the normal direction, the eccentric cam rotating the base member around the rotation axis by engaging with the cam follower;
A worm wheel that rotates integrally with the eccentric cam on the same axis;
The worm meshes with the worm wheel, and a worm along an orthogonal direction orthogonal to the normal direction,
A motor that drives the eccentric cam by having a drive shaft along the orthogonal direction, and transmitting the driving force to the worm wheel by rotating the worm as the drive shaft rotates;
It is a roll paper conveying apparatus characterized by including.

  Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

1 is a schematic diagram illustrating a configuration of an image recording apparatus 1. FIG. 1 is a block diagram illustrating a configuration of an image recording apparatus 1. FIG. It is a perspective view of the guide unit 20a. It is a top view of the guide unit 20a. It is a rear view of the guide unit 20a. It is a side view of the guide unit 20a. It is a figure explaining operation | movement of the guide unit 20a.

At least the following matters will become apparent from the description of the present specification and the accompanying drawings.
That is, the roll paper is transported along the transport direction, and the first roller and the second roller arranged along the transport direction;
A base member that rotatably supports the first roller and the second roller around each central axis;
A rotation shaft that rotatably supports the base member along a normal direction of a virtual plane including the central axis of each of the first roller and the second roller;
A cam follower provided on the base member and protruding in the normal direction;
An eccentric cam that rotates around a central axis along the normal direction, the eccentric cam rotating the base member around the rotation axis by engaging with the cam follower;
A worm wheel that rotates integrally with the eccentric cam on the same axis;
The worm meshes with the worm wheel, and a worm along an orthogonal direction orthogonal to the normal direction,
A motor that drives the eccentric cam by having a drive shaft along the orthogonal direction, and transmitting the driving force to the worm wheel by rotating the worm as the drive shaft rotates;
It is a roll paper conveying apparatus characterized by including.
According to such a roll paper conveying device, the axial directions of the eccentric cam, the cam follower, and the worm wheel are arranged along the normal direction, and the axial directions of the motor and the worm are arranged along the orthogonal direction. Therefore, the thickness can be reduced as a whole.

In addition, such a roll paper transport device,
The first roller is located closer to the rotation axis than the second roller in the transport direction,
The worm may be positioned closer to the first roller than the worm wheel in the transport direction.
According to such a roll paper conveyance device, the position where the worm and the worm wheel mesh with each other is located near the first roller, so that the overall length in the conveyance direction can be shortened.

In addition, such a roll paper transport device,
The drive shaft of the motor may be along the central axis of each of the first roller and the second roller.
According to such a roll paper conveyance device, since the motor is arranged along the central axis of each of the first roller and the second roller, the length in the conveyance direction can be shortened as a whole.

In addition, such a roll paper transport device,
The motor and the worm are aligned in the orthogonal direction,
The cam follower and the eccentric cam are aligned in the orthogonal direction,
The eccentric cam and the worm are aligned in the transport direction,
When the orthogonal direction from the worm to the motor is the first direction, the cam follower may be positioned downstream of the eccentric cam in the first direction.
According to such a roll paper transport device, the length in the orthogonal direction can be shortened as a whole.

In addition, the roll paper is transported along the transport direction, and the first roller and the second roller arranged along the transport direction,
A base member that rotatably supports the first roller and the second roller around each central axis;
A rotation shaft that rotatably supports the base member along a normal direction of a virtual plane including the central axis of each of the first roller and the second roller;
A cam follower provided on the base member and protruding in the normal direction;
An eccentric cam that rotates around a central axis along the normal direction, the eccentric cam rotating the base member around the rotation axis by engaging with the cam follower;
A worm wheel that rotates integrally with the eccentric cam on the same axis;
The worm meshes with the worm wheel, and a worm along an orthogonal direction orthogonal to the normal direction,
A motor that drives the eccentric cam by having a drive shaft along the orthogonal direction, and transmitting the driving force to the worm wheel by rotating the worm as the drive shaft rotates;
A roll paper transport method comprising transporting the roll paper using a roll paper transport device comprising:
According to such a roll paper conveying method, the axial directions of the eccentric cam, the cam follower, and the worm wheel are arranged along the normal direction, and the axial directions of the motor and the worm are arranged along the orthogonal direction. Therefore, the thickness can be reduced as a whole.

In addition, the roll paper is transported along the transport direction, and the first roller and the second roller arranged along the transport direction, and the first roller and the second roller are rotatably supported around the respective central axes. A base member, a rotation shaft that rotatably supports the base member along a normal direction of a virtual plane including the central axis of each of the first roller and the second roller, and provided on the base member A cam follower projecting in the normal direction, and an eccentric cam that rotates around a central axis along the normal direction, and is engaged with the cam follower so that the base is centered on the rotation axis. An eccentric cam that rotates the member, a worm wheel that rotates integrally with the eccentric cam, and a gear that meshes with the worm wheel and that is orthogonal to the normal direction. A motor having a drive shaft along the orthogonal direction and rotating the worm as the drive shaft rotates to transmit a driving force to the worm wheel, thereby driving the eccentric cam; A roll paper transport device comprising:
A nozzle for discharging liquid, and a head for discharging liquid from the nozzle to a portion of the roll paper transported onto the image recording region by the roll paper transport device;
An image recording apparatus comprising:
According to such an image recording apparatus, the axial directions of the eccentric cam, the cam follower, and the worm wheel are arranged along the normal direction, and the axial directions of the motor and the worm are arranged along the orthogonal direction. Therefore, the thickness can be reduced as a whole.

=== Embodiment ===
Hereinafter, an image recording apparatus 1 according to an embodiment of the present invention will be described.

<<< Example of Configuration of Image Recording Apparatus 1 >>>
A configuration example of the image recording apparatus 1 will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic sectional view of the image recording apparatus 1. FIG. 2 is a block diagram of the image recording apparatus 1.
In the following description, when referring to “up and down direction” and “left and right direction”, the direction indicated by the arrow in FIG. 1 is used as a reference. In addition, the “front-rear direction” refers to a direction orthogonal to the paper surface in FIG.
Further, in the present embodiment, a description will be given using paper or film wound in a roll shape (hereinafter referred to as roll paper (continuous paper)) as a recording medium on which the image recording apparatus 1 records an image.

  As shown in FIGS. 1 and 2, the image recording apparatus 1 according to the present embodiment includes a transport unit 20 as an example of a roll paper transport device, and a transport path through which the transport unit 20 transports the roll paper 2. A head unit for recording an image in the image recording region R on the transport path, and a platen 29 as an example of a medium support unit, and a winding unit 90. 30, a carriage unit 40 as an example of a head moving unit, a heater unit 70 as an example of a heat supply unit, a blower unit 80 for sending air to the roll paper 2 on the platen 29, and these units, etc. A controller 60 that controls the operation of the image recording apparatus 1 and a detector group 50 are included.

  The feeding unit 10 feeds the roll paper 2 to the transport unit 20. The feeding unit 10 includes a winding shaft 18 around which the roll paper 2 is wound and rotatably supported, a relay roller 19 for winding the roll paper 2 fed from the winding shaft 18 and guiding the roll paper 2 to the transport unit 20; have.

  The transport unit 20 transports the roll paper 2 sent by the feeding unit 10 along a preset transport path. As shown in FIG. 1, the transport unit 20 includes a relay roller 21 that is positioned horizontally to the right of the relay roller 19, a relay roller 22 that is positioned obliquely downward to the right when viewed from the relay roller 21, and the relay roller 22. The first transport roller 23 located on the upper right side as viewed from the platen 29 (upstream in the transport direction as viewed from the platen 29), the guide unit 20a positioned between the relay roller 22 and the first transport roller 23, and the first transport From the second transport roller 24 positioned on the right side when viewed from the roller 23 (on the downstream side in the transport direction when viewed from the platen 29), the reverse roller 25 positioned vertically downward as viewed from the second transport roller 24, and the reverse roller 25 The relay roller 26 is located on the right side when viewed, and the delivery roller 27 is located on the upper side when viewed from the relay roller 26. The guide unit 20a will be described in detail later.

  The relay roller 21 is a roller that winds the roll paper 2 sent from the relay roller 19 from the left side and loosens it downward.

  The relay roller 22 is a roller that winds the roll paper 2 sent from the relay roller 21 from the left side and conveys it obliquely upward to the right.

  The first transport roller 23 includes a first drive roller 23a driven by a motor (not shown), and a first driven roller 23b arranged to face the first drive roller 23a with the roll paper 2 interposed therebetween. have. The first transport roller 23 is a roller that pulls up the roll paper 2 slacked downward and transports it to the image recording region R facing the platen 29. The first conveyance roller 23 temporarily stops conveyance during a period in which image printing is performed on the portion of the roll paper 2 on the image recording region R. In addition, when the first driven roller 23b rotates as the first drive roller 23a rotates by the drive control of the controller 60, the transport amount of the roll paper 2 positioned on the platen 29 (the length of the portion of the roll paper) Is adjusted).

  As described above, the transport unit 20 has a mechanism for transporting the portion of the roll paper 2 wound between the relay rollers 21 and 22 and the first transport roller 23 by slacking it downward. The slackness of the roll paper 2 is monitored by the controller 60 based on a detection signal from a slack detection sensor (not shown). Specifically, when a portion of the roll paper 2 slackened between the relay rollers 21 and 22 and the first transport roller 23 is detected by the slack detection sensor, a tension of an appropriate magnitude is applied to the portion. Therefore, the transport unit 20 can transport the roll paper 2 in a relaxed state. On the other hand, when the portion of the roll paper 2 that has been loosened is not detected by the slack detection sensor, an excessive amount of tension is applied to the portion, and therefore the transport of the roll paper 2 by the transport unit 20 is temporarily performed. And the tension is adjusted to an appropriate level.

  The second transport roller 24 includes a second drive roller 24a driven by a motor (not shown), and a second driven roller 24b disposed so as to face the second drive roller 24a with the roll paper 2 interposed therebetween. have. The second transport roller 24 is a roller that transports the portion of the roll paper 2 on which the image is recorded by the head unit 30 in the horizontal right direction along the support surface of the platen 29 and then transports it vertically downward. Thereby, the conveyance direction of the roll paper 2 is changed. The second driven roller 24b rotates as the second drive roller 24a is driven to rotate by the drive control of the controller 60, whereby a predetermined amount given to the portion of the roll paper 2 located on the platen 29 is obtained. Tension is adjusted.

  The reversing roller 25 is a roller that wraps the roll paper 2 sent from the second conveying roller 24 from the upper left side and conveys it diagonally upward to the right.

  The relay roller 26 is a roller that winds the roll paper 2 sent from the reversing roller 25 from the lower left side and conveys it upward.

  The delivery roller 27 winds the roll paper 2 sent from the relay roller 26 from the lower left side and sends it to the take-up unit 90.

  As described above, the roll paper 2 moves sequentially through the rollers, whereby a transport path for transporting the roll paper 2 is formed. The roll paper 2 is intermittently transported along the transport path by the transport unit 20 in units of regions corresponding to the image recording regions R.

  The head unit 30 is for ejecting ink onto a portion of the roll paper 2 that has been fed into the image recording region R on the transport path (on the platen 29) by the transport unit 20. The head unit 30 has a head 31 and a valve unit 34.

  The head 31 has a nozzle row composed of a plurality of nozzles # 1 to # 180 for each color such as yellow (Y), magenta (M), cyan (C), and black (K) on the lower surface thereof. . The head 31 performs flushing for each nozzle row during flushing.

  The nozzles # 1 to # 180 of each nozzle row are arranged in a straight line along the direction intersecting the transport direction of the roll paper 2. Each nozzle row is arranged in parallel with a space between each other along the moving direction (scanning direction) of the head 31. Each nozzle # 1 to # 180 is provided with a piezo element (not shown) as a drive element for ejecting ink droplets. When a voltage having a predetermined time width is applied between the electrodes provided at both ends of the piezoelectric element, the piezoelectric element expands according to the voltage application time and deforms the side wall of the ink flow path. As a result, the volume of the ink flow path contracts according to the expansion and contraction of the piezo element, and the ink corresponding to the contraction is ejected from the nozzles # 1 to # 180 of each color as ink droplets.

  The valve unit 34 is for temporarily storing ink, and is connected to the head 31 via an ink supply tube (not shown). For this reason, the head 31 can perform image printing by discharging the ink supplied from the valve unit 34 toward the portion of the roll paper 2 that has been transported from the nozzle onto the platen 29 and stopped. .

  The carriage unit 40 is for moving the head 31. The carriage unit 40 includes a guide rail 41 extending in the left-right direction (indicated by a two-dot chain line in FIG. 1), a carriage 42 supported so as to reciprocate in the left-right direction (movement direction) along the guide rail 41, And a motor shown in the figure.

  The carriage 42 is configured to move integrally with the head 31 by driving a motor (not shown). The position of the carriage 42 (the head 31 or each nozzle row) on the guide rail 41 (the position in the left-right direction) is determined by the rising edge and the falling edge in the pulse signal output from the encoder provided in the motor (not shown) by the controller 60. It can be obtained by detecting and counting this edge.

  Then, when cleaning the head 31 after image printing, the carriage 42 moves together with the head 31 along the guide rail 41 to the upstream side in the transport direction (upstream in the transport direction as viewed from the platen 29). It stops at the home position HP for cleaning (see FIG. 1).

  A cleaning unit (not shown) is provided at the home position HP. This cleaning unit has a cap, a suction pump, and the like. When the carriage 42 is positioned at the home position HP, a cap (not shown) is in close contact with the lower surface (nozzle surface) of the head 31. When the suction pump (not shown) is operated with the cap in close contact, the ink in the head 31 is sucked together with the thickened ink and paper powder. In this way, the clogged nozzle recovers from the non-ejection state, thereby completing the head cleaning.

  Further, when flushing the head 31 after printing an image, the carriage 42 moves together with the head 31 from the platen 29 side toward the home position HP side. At this time, the head 31 performs a flushing operation in the flushing unit 35 disposed between the platen 29 and the home position HP while moving together with the carriage 42.

  The platen 29 supports the part of the roll paper 2 located in the image recording region R on the conveyance path and heats the part. As shown in FIG. 1, the platen 29 is provided corresponding to the image recording area R on the conveyance path, and is an area along the conveyance path between the first conveyance roller 23 and the second conveyance roller 24. Is arranged. The platen 29 can heat the portion of the roll paper 2 by receiving supply of heat generated by the heater unit 70.

  The heater unit 70 is for heating the roll paper 2 and has a heater (not shown). This heater has a nichrome wire, and the nichrome wire is arranged inside the platen 29 so as to be at a fixed distance from the support surface of the platen 29. For this reason, when the heater is energized, the nichrome wire itself generates heat, and heat can be conducted to the portion of the roll paper 2 located on the support surface of the platen 29. Since this heater is configured by incorporating a nichrome wire in the entire area of the platen 29, heat can be uniformly conducted to the portion of the roll paper 2 on the platen 29. In the present embodiment, the portion of the roll paper 2 is uniformly heated so that the temperature of the portion of the roll paper 2 on the platen is 45 ° C. Thereby, the ink landed on the part of the roll paper 2 can be dried.

  The blower unit 80 includes a fan 81 as an example of a blower and a motor (not shown) that rotates the fan 81. The fan 81 rotates to send wind to the roll paper 2 on the platen 29 and dry the ink landed on the roll paper 2. As shown in FIG. 1, a plurality of fans 81 are provided on an openable / closable cover (not shown) provided on the main body. Each fan 81 is positioned above the platen 29 when the cover is closed, and faces the support surface of the platen 29 (the roll paper 2 on the platen 29).

  The winding unit 90 is for winding the roll paper 2 (image-printed roll paper) sent by the transport unit 20. This take-up unit 90 is fed from the relay roller 91 that is rotatably supported by the relay roller 91 for winding the roll paper 2 sent from the feed roller 27 from the upper left side and conveying it to the lower right side. And a take-up drive shaft 92 for taking up the roll paper 2.

  The controller 60 is a control unit for controlling the image recording apparatus 1. As shown in FIG. 2, the controller 60 includes an interface unit 61, a CPU 62, a memory 63, and a unit control circuit 64. The interface unit 61 is for transmitting and receiving data between the host computer 110 as an external device and the image recording apparatus 1. The CPU 62 is an arithmetic processing device for controlling the entire image recording apparatus 1. The memory 63 is for securing an area for storing a program of the CPU 62, a work area, and the like. The CPU 62 controls each unit by a unit control circuit 64 according to a program stored in the memory 63.

  The detector group 50 monitors the situation in the image recording apparatus 1. For example, the detector group 50 is attached to a conveyance roller and used for control such as conveyance of the roll paper 2, and the roll paper 2 to be conveyed. There are a paper detection sensor for detecting the presence or absence of the paper, a linear encoder for detecting the position of the carriage 42 (or head 31) in the moving direction (left-right direction), an edge detection sensor for detecting the edge of the roll paper 2, and the like.

<<< About the Guide Unit 20a >>>
<Position adjustment in the width direction of roll paper>
The guide unit 20a has a function (positioning function) for adjusting the position of the roll paper 2 in the width direction.

  When the roll paper 2 is transported along the transport path, the position in the width direction of the roll paper is displaced due to fluctuations in the tension acting on the roll paper due to misalignment of the relay roller or an assembly error. There is. In addition, due to a telescope phenomenon in which the roll paper is misaligned when the roll paper is attached to the feeding machine (feeding unit), the width dimension of the roll paper itself changes, and the end face of the roll paper is inclined. In some cases, the position of the roll paper in the width direction may change.

  As described above, when the position of the roll paper in the width direction is largely deviated, the printing position on the roll paper is also largely deviated, resulting in printing failure. In addition, a piece of paper or a paper jam may occur.

  In such a case, the guide unit 20a can adjust the position in the width direction of the roll paper 2 while guiding the roll paper 2 along the conveyance path, and thus it is possible to suppress the occurrence of printing defects and the like.

<About the arrangement in the image recording apparatus>
As described above, the image recording apparatus 1 according to the present embodiment includes various units such as the transport unit 20, and some of these units are arranged inside the apparatus.

  Since the space inside the apparatus is limited, it is necessary to efficiently lay out these units in the limited space.

  Here, as one of the units arranged in the space in the apparatus, there is a guide unit 20a that the transport unit 20 has (see FIG. 1).

  The guide unit 20a is composed of a plurality of members including a motor and the like (details will be described later) in order to exert a function of adjusting the position of the roll paper 2 in the width direction. Depending on the combination and arrangement (structure) of these members, the guide unit 20a may increase the thickness of the unit (the height of the unit itself may increase).

  In particular, when the guide unit 20a is arranged in the image recording apparatus 1, the guide unit 20a occupies a large space in the apparatus as the thickness of the guide unit 20a increases. May not be able to be stored compactly.

  Further, as the thickness of the guide unit 20a increases, the possibility of contact with other units increases. Therefore, the guide unit 20a needs to be laid out while avoiding the contact. As a result of the contact avoidance, the transport path for transporting the roll paper may be complicated.

  Therefore, it is desirable that the height of the guide unit 20a disposed in the image recording apparatus 1 be as low as possible.

  On the other hand, in the roll paper transport device in the image recording apparatus 1 according to the present embodiment, the thickness of the guide unit 20a is made as thin as possible by adopting a specific configuration described later. Thereby, since the guide unit 20a can be reduced in size, it can be stored in the image recording apparatus in a compact manner.

  Hereinafter, the guide unit 20a included in the roll paper conveyance device of the image recording apparatus 1 according to the present embodiment will be specifically described.

<About configuration example>
Here, a configuration example of the guide unit 20a will be described with reference to FIGS. FIG. 3 is a perspective view of the guide unit 20a. FIG. 4 is a plan view of the guide unit 20a. FIG. 5 is a rear view of the guide unit 20a. FIG. 6 is a side view of the guide unit 20a. The coil spring 209 in the present embodiment is formed by spirally winding a metal wire having a predetermined wire diameter by a predetermined number of turns. In FIGS. 3 to 6, for convenience, the coil spring 209 is formed. The external appearance shape is simplified and illustrated.

  As shown in FIG. 1, the guide unit 20 a is positioned on the transport path in an inclined state, and adjusts the position of the roll paper 2 in the width direction (front-rear direction shown in FIG. 1).

  As shown in FIGS. 3 to 6, the guide unit 20a includes a first roller 201 and a second roller 202, and a first roller 201 and a second roller 202 for conveying the roll paper 2 in the conveying direction. A base member 203 rotatably supported around the central shafts 201a and 202a; an eccentric cam 204 for rotating the base member 203 around the rotation shaft 203a; and a motor 205 as an example of a drive unit. doing.

  The first roller 201 and the second roller 202 are configured to be rotatable around their respective central axes 201a and 202a, and are arranged in parallel in the transport direction as shown in FIG.

  As shown in FIG. 1, the first roller 201 is located on the upstream side of the second roller 202 in the transport direction, and rolls the roll paper 2 sent from the relay roller 22 from above and below the second roller 202. It is the roller which conveys toward.

  As shown in FIG. 1, the second roller 202 is positioned downstream in the transport direction from the first roller 201, and rolls the roll paper 2 sent from the first roller 201 from below, It is a roller that conveys toward one conveyance roller 23.

  As shown in FIGS. 5 and 6, the base member 203 is centered on the rotation shaft 203 a above the base 200 fixed to the image recording apparatus 1 by the rotation shaft 203 a and the two movable support portions 210. And is rotatably supported.

  The rotation shaft 203 a supports the base member 203 so as to be rotatable with respect to the base 200. As shown in FIGS. 4 and 6, the rotation shaft 203 a is positioned closer to the first roller 201 than the second roller 202 in the transport direction, and the central shaft 201 a of the first roller 201 and the second roller 202 Are fixed to the base 200 along the normal direction of a virtual plane including the central axis 202a.

  As shown in FIGS. 4 and 6, the movable support portion 210 is attached to the lower surface of the base member 203, and moves while the base member 203 moves around the rotation shaft 203a. The member 203 is supported. Therefore, the movable support part 210 moves on a circular orbit centering on the rotation shaft 203a. Further, as shown in FIGS. 5 and 6, the movable support portion 210 includes an L-shaped bracket 210a fixed to the lower surface of the base member 203, and a wheel 210b rotatably provided at the tip of the L-shaped bracket 210a. have.

  The number of wheels 210b need not be limited to this, and it is sufficient that at least two wheels 210b exist. That is, the base member 203 only needs to be provided with at least two movable support portions 210.

  Further, as shown in FIG. 5, the movement of the wheel 210b in a direction away from the moving surface (base 200) is restricted by the restriction member 211. For this reason, even if the wheel 210b moves away from the moving surface due to an assembly error or the like, the wheel 210b may move while the upper portion thereof is in contact with the regulating member 211 as the base member 203 rotates. Is possible. In this embodiment, as shown in FIGS. 5 and 6, an L-shaped bracket arranged in an inverted L-shape is employed as an example of the regulating member 211.

  The motor 205 is fixed on the base 200 via a bracket and is driven based on a control signal from the controller 60 to rotate the base member 203. The motor 205 has a rotary encoder (not shown) for detecting a rotation angle and a rotation speed.

  As shown in FIG. 4, the drive shaft 205a of the motor 205 is connected to the transmission shaft 205c via a coupling 205b, and a worm (screw gear) 206 is fitted to the transmission shaft 205c. The transmission shaft 205 c is supported at both ends by bearings 205 d fixed to the base 200.

  As shown in FIG. 4, the drive shaft 205a of the motor in the present embodiment is along an orthogonal direction orthogonal to the normal direction of the above-described virtual plane. That is, the drive shaft 205a of the motor is along the central axes 201a and 202a of the first roller 201 and the second roller 202 arranged in the transport direction. As a result, the motor 205 is disposed in a state where it is laid down in the longitudinal direction of the base member 203, and therefore can fit within a narrow space (a space having a height A, see FIG. 5) below the base member 203. It can be done. For this reason, the length of the conveyance direction can be shortened as a whole guide unit 20a.

  As shown in FIG. 4, the worm 206 is arranged in a direction along the above-described orthogonal direction (arranged coaxially with the drive shaft 205 a of the motor), and a worm wheel (helical gear) 207 described later. Are engaged. The worm 206 receives the driving force of the motor 205 transmitted through the drive shaft 205a and the coupling 205b, and rotates around the transmission shaft 205c. Therefore, when the worm 206 rotates, the worm wheel 207 that meshes with the worm 206 also starts rotating.

  The worm 206 in the present embodiment is located closer to the first roller 201 than the worm wheel 207 in the transport direction. That is, the position where the worm 206 and the worm wheel 207 mesh with each other is located near the first roller 201. The reason for this configuration is as follows.

  For example, in order to increase the positioning accuracy of the guide unit 20a, assuming that the position where the rotational force acts on the base member 203 (the position of the cam follower 208 relative to the base member 203) is assumed, the worm 206 is assumed to be If the worm wheel 207 is located farther from the first roller 201 than the worm wheel 207 in the transport direction, the worm 206, the motor 205, and the like are located downstream of the second roller 202, and therefore the entire guide unit 20a. This is because the length in the transport direction becomes long. Therefore, in the guide unit 20a in the present embodiment, the above-described configuration is effective in achieving compactness as a whole.

  As shown in FIG. 4, the worm wheel 207 rotates coaxially with the eccentric cam 204 when the driving force of the motor 205 transmitted via the worm 206 acts.

  Thus, in the guide unit 20a in the present embodiment, by using the worm 206 and the worm wheel 207 to decelerate, a large torque can be transmitted even if the motor 205 is small.

  The eccentric cam 204 is for rotating the base member 203 around the rotation shaft 203a by rotating around the central axis 204a along the normal direction. As shown in FIGS. 4 and 5, the eccentric cam 204 is in contact with the cam follower 208 provided on the lower surface of the base member 203 on the outer peripheral surface thereof. The cam follower 208 is always urged in a direction in which the cam follower 208 is pressed against the eccentric cam 204 by the coil spring 209. For this reason, the eccentric cam 204 engages with the cam follower 208 along with the rotating operation when the driving force of the motor 205 is transmitted and the rotating operation is performed coaxially with the worm wheel 207. Thus, the base member 203 can be rotated around the rotation shaft 203a. In addition, the eccentric cam 204 is not located on the opposite side of the first roller 201 with the second roller 202 interposed in the conveyance direction of the roll paper 2 during the rotation operation, and at least a part of the eccentric cam 204. Is opposed to the second roller 202 in the normal direction of the virtual plane (virtual plane including the central axes 201a and 202a of the first roller 201 and the second roller 202, respectively). That is, as shown in FIG. 4, the eccentric cam 204 does not protrude downstream from the second roller 202 in the transport direction, and faces the second roller 202 with the base member 203 interposed therebetween (paper surface). It is positioned so as to overlap the second roller 202 above. Accordingly, since the driving force acts at the position of the second roller 202 far from the position of the rotation shaft 203a while avoiding the contact between the eccentric cam 204 and the roll paper 2, the positioning accuracy in the width direction of the roll paper 2 Can be increased.

  As shown in FIGS. 4 and 6, the cam follower 208 is provided so as to protrude in the normal direction (is provided so as to protrude on the lower surface of the base member 203), and by engaging with the eccentric cam 204, As the member 203 rotates, the member 203 rotates around the rotation shaft 203a.

  In the present embodiment, as shown in FIG. 4, the motor 205 and the worm 206 are arranged in the orthogonal direction, the cam follower 208 and the eccentric cam 204 are arranged in the orthogonal direction, and the eccentric cam 204 and the worm 206 are further conveyed in the conveying direction. When the orthogonal direction from the worm 206 to the motor 205 is the first direction, the cam follower 208 is positioned downstream of the eccentric cam 204 in the first direction. The reason for this configuration is as follows.

  For example, in order to improve the positioning accuracy of the guide unit 20a, it is assumed that the position where the rotational force acts on the base member 203 (the position of the cam follower 208 with respect to the base member 203) is maintained. If the motor 205 is positioned upstream of the eccentric cam 204 in the first direction, the motor 205 will not fit in the space below the base member 203 and will protrude, so the entire guide unit will be orthogonal. This is because the length becomes long. Therefore, in the guide unit 20a in the present embodiment, the above-described configuration is effective in achieving compactness as a whole.

  As shown in FIG. 5, the coil spring 209 as an example of the elastic member has one end fixed to the base member 203 via the L-shaped bracket 209a and the other end positioned to the base via the L-shaped bracket 209b. A tension spring fixed to 200. Accordingly, the coil spring 209 can be biased in a direction in which the cam follower 208 is pressed against the eccentric cam 204. Further, as shown in FIG. 4, the coil spring 209 is disposed along the tangential direction of a circle centered on the rotation shaft 203a, and therefore, the base member 203 that performs a circular motion about the rotation shaft 203a is provided. On the other hand, the spring force can be transmitted most efficiently.

  As described above, in the roll paper conveyance device of the image recording apparatus 1 according to the present embodiment, the axial directions of the eccentric cam 204, the worm wheel 207, and the cam follower 208 are aligned along the normal direction that coincides with the rotation shaft 203a. In addition, by aligning the axial directions of the motor 205 and the worm 206 along the orthogonal direction perpendicular to the normal direction, the thickness of the entire guide unit can be reduced.

  Further, the guide unit 20a has an eccentric cam 204, a motor 205, a worm 206, a worm wheel 207, a cam follower 208, a coil spring 209, and a movable member in a space below the base member 203 (a space having a height A, see FIG. 5). Since the first roller 201 and the second roller 202 are configured to be supported above the base member 203 in a state in which the support portion 210 and the like are accommodated, the overall size can be reduced.

<Operation example>
Next, an operation example of the guide unit 20a will be described with reference to FIG. FIG. 7 is a diagram for explaining an operation example of the guide unit 20a.
Various operations of the image recording apparatus 1 are realized mainly by the controller 60. In particular, in the present embodiment, it is realized by the CPU 62 or the like processing a program stored in the memory 63. And this program is comprised from the code | cord | chord for performing the various operation | movement demonstrated below.

  When a control signal from the host computer 110 is input to the controller 60 via the interface unit 61, the controller 60 detects a detection signal from an edge detection sensor 50 a that detects the edge of the roll paper 2 while the roll paper 2 is being conveyed. Based on the above, it is determined whether or not the positional deviation in the width direction of the roll paper 2 occurs.

  Next, when the controller 60 determines that the roll paper 2 is displaced upward in the width direction (see FIG. 7), the controller 60 performs drive control of the motor 205 so that the eccentric cam 204 rotates clockwise.

  When the eccentric cam 204 rotates clockwise, the cam follower 208 pressed against the eccentric cam 204 by the urging force of the coil spring 209 reduces the distance between the centers of the eccentric cam 204 and the circle about the rotation shaft 203a. It moves clockwise along the trajectory (see FIG. 4).

  Then, since the cam follower 208 is attached to the base member 203, the base member 203 also rotates clockwise about the rotation shaft 203a, and the roll paper 2 is lowered in the width direction (see FIG. 7). Try to position. Thereby, the position in the width direction of the roll paper 2 is corrected.

  On the other hand, if the controller 60 determines that the roll paper 2 is displaced downward in the width direction (see FIG. 7), the controller 60 controls the drive of the motor 205 so that the eccentric cam 204 rotates counterclockwise. Do.

  When the eccentric cam 204 rotates counterclockwise, the cam follower 208 pressed against the eccentric cam 204 by the biasing force of the coil spring 209 rotates against the biasing force while increasing the distance between the centers of the eccentric cam 204 and the cam follower 208. It moves counterclockwise along a circular orbit centered on the moving shaft 203a (see FIG. 4).

  Then, since the base member 203 also rotates counterclockwise about the rotation shaft 203a, the roll paper 2 tends to be positioned on the upper side in the width direction (see FIG. 7). Thereby, the position in the width direction of the roll paper is corrected.

  When the controller 60 receives a detection signal from the limit sensor 212 while the base member 203 is rotating, the controller 60 performs control to stop driving the motor 205 so that the base member 203 does not rotate any more. To do.

  As described above, the position of the roll paper 2 in the width direction can be adjusted by performing such operation control on the guide unit 20a of the image recording apparatus 1 according to the present embodiment.

=== Other Embodiments ===
Although the present embodiment is mainly described with respect to an image recording apparatus, disclosure of a liquid ejection method and the like is also included. Further, the present embodiment is intended to facilitate understanding of the present invention and is not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and it is needless to say that the present invention includes equivalents thereof. In particular, the embodiments described below are also included in the present invention.

<Image recording device>
In the above embodiment, an ink jet printer has been described as an example of the image recording apparatus, but the present invention is not limited to this. For example, an image recording apparatus that ejects liquid other than ink may be used. The present invention can be used for various image recording apparatuses including a liquid jet head that discharges a minute amount of liquid droplets. The droplet means a state of the liquid ejected from the image recording apparatus, and includes a liquid having a granular shape, a tear shape, or a thread shape. The liquid here may be any material that can be discharged by the image recording apparatus. For example, it may be in a state in which the substance is in a liquid phase, such as a liquid with high or low viscosity, sol, gel water, other inorganic solvents, organic solvents, solutions, liquid resins, liquid metals (metal melts ) And a liquid as one state of a substance, as well as a material in which particles of a functional material made of a solid such as a pigment or metal particles are dissolved, dispersed or mixed in a solvent. Further, representative examples of the liquid include ink and liquid crystal as described in the above embodiment. Here, the ink includes general water-based inks and oil-based inks, and various liquid compositions such as gel inks and hot melt inks. As a specific example of the image recording apparatus, for example, a liquid containing a material such as an electrode material or a color material used for manufacturing a liquid crystal display, an EL (electroluminescence) display, a surface emitting display, or a color filter in a dispersed or dissolved form. It may be an image recording apparatus that discharges, an image recording apparatus that discharges bioorganic materials used in biochip manufacturing, an image recording apparatus that discharges liquid as a sample used as a precision pipette, a textile printing apparatus, a microdispenser, or the like. In addition, transparent resin liquids such as UV curable resins to form image recording devices that pinpoint lubricants to precision machines such as watches and cameras, and micro hemispherical lenses (optical lenses) used in optical communication elements. An image recording apparatus that discharges the liquid onto the substrate or an image recording apparatus that discharges an etching solution such as an acid or an alkali to etch the substrate may be employed. The present invention can be applied to any one of these image recording apparatuses.

1 image recording device, 2 roll paper,
10 Feeding unit, 18 winding shaft, 19 relay roller,
20 transport unit, 20a guide unit,
21 relay roller, 22 relay roller,
23 1st conveyance roller, 24 2nd conveyance roller,
25 reversing roller, 26 relay roller, 27 delivery roller,
29 platens, 30 head units, 31 heads,
34 valve unit, 35 flushing unit,
40 carriage unit, 41 guide rail, 42 carriage,
50 detector groups, 60 controllers, 70 heater units,
80 blower unit, 81 fan, 90 take-up unit,
91 relay roller, 92 winding drive shaft,
110 host computers, 200 bases,
201 first roller, 201a central axis,
202 second roller, 202a central axis,
203 base member, 203a rotating shaft,
204 eccentric cam, 204a central axis,
205 motor, 205a drive shaft, 205b coupling,
205c transmission shaft, 205d bearing,
206 Worm, 207 Worm wheel,
207a central axis, 208 cam follower,
209 Coil spring, 209a L-shaped bracket,
209b L-shaped bracket, 210 movable support,
210a L-shaped bracket, 210b wheel,
211 restricting member, 212 limit sensor

Claims (5)

A roll paper is conveyed along the conveyance direction, and a first roller and a second roller arranged along the conveyance direction;
A base member that rotatably supports the first roller and the second roller around each central axis;
A rotation shaft that rotatably supports the base member along a normal direction of a virtual plane including the central axis of each of the first roller and the second roller;
A cam follower provided on the base member and protruding in the normal direction;
An eccentric cam that rotates around a central axis along the normal direction, the eccentric cam rotating the base member around the rotation axis by engaging with the cam follower;
A worm wheel that rotates integrally with the eccentric cam on the same axis;
The worm meshes with the worm wheel, and a worm along an orthogonal direction orthogonal to the normal direction,
A drive shaft along the perpendicular direction, by transmitting a driving force to the worm wheel by rotating said worm with the rotation of the drive shaft, e Bei and a motor for driving the eccentric cam,
The first roller is located closer to the rotation axis than the second roller in the transport direction,
The worm is positioned closer to the first roller than the worm wheel in the transport direction;
A roll paper conveying apparatus characterized by the above. The roll paper transport device according to claim 1 ,
The roll paper transport device, wherein a drive shaft of the motor is along a central axis of each of the first roller and the second roller. It is a roll paper conveying apparatus of Claim 2 , Comprising:
The motor and the worm are aligned in the orthogonal direction,
The cam follower and the eccentric cam are aligned in the orthogonal direction,
The eccentric cam and the worm are aligned in the transport direction,
When the orthogonal direction from the worm to the motor is a first direction, the cam follower is located downstream of the eccentric cam in the first direction.
A roll paper conveying apparatus characterized by the above. A roll paper is conveyed along the conveyance direction, and a first roller and a second roller arranged along the conveyance direction;
A base member that rotatably supports the first roller and the second roller around each central axis;
A rotation shaft that rotatably supports the base member along a normal direction of a virtual plane including the central axis of each of the first roller and the second roller;
A cam follower provided on the base member and protruding in the normal direction;
An eccentric cam that rotates around a central axis along the normal direction, the eccentric cam rotating the base member around the rotation axis by engaging with the cam follower;
A worm wheel that rotates integrally with the eccentric cam on the same axis;
The worm meshes with the worm wheel, and a worm along an orthogonal direction orthogonal to the normal direction,
A drive shaft along the perpendicular direction, by transmitting a driving force to the worm wheel by rotating said worm with the rotation of the drive shaft, e Bei and a motor for driving the eccentric cam,
The first roller is located closer to the rotation axis than the second roller in the transport direction,
The worm is positioned closer to the first roller than the worm wheel in the transport direction;
Using a roll paper transportation device according to claim, roll paper transportation method characterized by conveying the roll paper. A base member that transports roll paper along the transport direction, and supports the first roller and the second roller that are aligned along the transport direction, and the first roller and the second roller so as to be rotatable around their respective central axes. And along the normal direction of a virtual plane including the central axis of each of the first roller and the second roller, a rotation shaft that rotatably supports the base member, and provided on the base member, A cam follower protruding in the normal direction, and an eccentric cam that rotates around a central axis along the normal direction, and the base member is moved around the rotation axis by engaging with the cam follower. An eccentric cam to be rotated, a worm wheel which is coaxially rotated integrally with the eccentric cam, and a worm wheel which meshes with the worm wheel and which extends along an orthogonal direction perpendicular to the normal direction. And a motor that drives the eccentric cam by transmitting a driving force to the worm wheel by rotating the worm as the drive shaft rotates, and a drive shaft along the orthogonal direction. The first roller is positioned closer to the pivot shaft than the second roller in the transport direction, and the worm is positioned closer to the first roller than the worm wheel in the transport direction. A roll paper transport device characterized by :
A nozzle for discharging liquid, and a head for discharging liquid from the nozzle to a portion of the roll paper transported onto the image recording region by the roll paper transport device;
An image recording apparatus comprising:

Images