[0001]The present invention relates to a recording apparatus comprising a recording medium conveying device and the recording medium transport device.
Background technique
[0002]Ink jet printer as a recording apparatus, the recording medium conveyed on the platen, operation for ejecting ink droplets from the recording head, a desired in the recording medium by alternately repeating the operation of moving the recording medium to record an image.
　Patent Document 1, the nip rollers consisting of a driving roller and a driven roller, positioned before and after the platen in the conveying path of the recording medium, sets the recording medium in a predetermined recording position on the platen, a predetermined amount by a nip roller while moving (pitch feed), and recording apparatus for recording is described an image in a desired range of the recording medium.
CITATION
Patent Document
[0003]
Patent Document 1: JP 2003-25664 JP
Summary of the Invention
Problems that the Invention is to Solve
[0004]
　However, in the recording apparatus disclosed in Patent Document 1, during the operation that records images in a desired range of the recording medium, because it continues to nip states before and after the recording medium of the platen, for example, the conveyance of the recording medium even if there is a misalignment in the path, during the recording operation of the image, there is a problem that can not be eliminated it. In particular, a long recording medium is a strip, when the length of the image to be recorded is longer along the recording medium, since the movement of the left recording medium maintaining the nip state until the recording of the image is completed continues, slight or a major shift misalignment of the recording medium is accumulated while continuing the recording, there is a case of or worse by generating wrinkles in the recording medium due to this deviation.
Means for Solving the Problems
[0005]
　The present invention has been made to solve at least part of the problems described above, and can be realized as the following applications or forms.
[0006]
　Application Example 1 A recording medium conveying apparatus according to this application example, a drive roller and a driven roller roller axis direction is parallel to each other, sandwiching a recording medium between said driven roller and said drive roller a recording medium conveying device for conveying the recording medium by at state driving the drive roller, the driven roller, is movably supported from the predetermined position in the roller axis direction, the driven roller, wherein when spaced apart from the driving roller without pinching the recording medium between the drive roller, wherein the driven roller is moved to the predetermined position in the roller axis direction.
[0007]
　According to this application example, the driven roller, because it is movably supported from the predetermined position in the roller axis direction, the recording medium may be a state of being held between the drive roller and the driven roller, the roller axis direction move to is easier. As a result, for example, even when the wrinkle is worked is likely roller shaft force generated in the recording medium, can be the response to the force, gradually recording medium with the conveyance is to move There, for example, can be positional deviation is eliminated and that wrinkles and accumulation occurs. The driven roller, when spaced from the drive roller without pinching the recording medium between the driving roller, since the driven roller is moved to a predetermined position in the roller axis direction, by a drive roller and a driven roller in the initial state for holding the recording medium, the driven roller is enabled to move from a predetermined position. For example, by making the center of the movable range of the predetermined position constraint is eliminated with respect to the moving direction.
[0008]
　Application Example 2 A recording medium conveying apparatus according to the application example, the driven roller, when in the roller axis direction is moved from the predetermined position, the driven roller is urged in a direction to return to the predetermined position and wherein the Rukoto.
[0009]
　According to this application example, the driven roller, when moving from the predetermined position in the roller axis direction, since the driven roller is urged in the direction to return to a predetermined position, the driven roller, the recording between the drive rollers apart from the driving roller without pinching the medium, if it becomes free, the driven roller is moved to a predetermined position in the roller axis direction. Therefore, in the initial state for holding the recording medium by the drive roller and the driven roller, the driven roller, it is possible to move from a predetermined position.
[0010]
　Application Example 3 A recording medium conveying apparatus according to the application example, the movement amount from the predetermined position of the driven roller in the roller axis direction and a detecting unit for detecting that reaches the maximum allowable amount of movement it is characterized in.
[0011]
　According to this application example, it is possible amount of movement from the predetermined position of the driven roller is detected that reaches the maximum allowable amount of movement. For example, if the driven roller is moved while eliminating the misalignment of the recording medium, the amount of movement is no longer able to overcome the misalignment reaches the maximum allowable amount of movement, performs the appropriate action based on the detection result it becomes possible.
[0012]
　Application Example 4 A recording medium conveying apparatus according to the application example, unwinding the recording medium housing the recording medium of the roll state recording medium unwinding unit and, unwound recording medium for taking up the recording medium characterized by comprising a winding section, the.
[0013]
　According to this application example, it is possible to convey to hold the recording medium supplied in roll state by the driving roller and the driven roller, also can be wound. The driven roller, because it is movably supported from the predetermined position in the roller axis direction, by the recording medium drive roller and the driven roller even when continued conveyance while pinching, a slight recording medium without misalignment is accumulated, it is possible to continue the conveyance while eliminating the deviation. As a result, to generate wrinkles in the recording medium is suppressed.
[0014]
　Application Example 5 In the recording medium conveying apparatus according to the application example, the maximum allowable amount of movement D, and the length of the conveying path of the recording medium from the recording medium unwinding unit to said recording medium winding unit L1 , when the length of the conveying path of the recording medium from the recording medium unwinding unit to a position where the recording medium is sandwiched between the driven roller and the drive roller L2, and, D ≦ 10 mm × L2 characterized in that it is a / L1.
[0015]
　According to this application example, when configured to transport path of the recording medium from the recording medium unwinding unit to the recording medium winding unit in a straight line when viewed deployed to the virtual plane, the recording medium winding unit the winding displacement in can be suppressed to 10mm or less.
[0016]
　Application Example 6 recording apparatus according to this application example is characterized by comprising a recording medium conveying apparatus according to the application example, and a recording unit that performs recording on the recording medium.
[0017]
　According to this application example, it is possible to perform the recording wrinkles of the recording medium due to misalignment and this has been suppressed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018]
Perspective view of a recording apparatus provided with a recording medium conveying apparatus according to [1] Embodiment 1.
Conceptual diagram showing a configuration of a recording apparatus provided with a recording medium conveying apparatus according to [2] Embodiment 1.
[Figure 3] a perspective view showing the configuration of a part of the transport unit.
[Figure 4] a front view as seen from the + Y side manner supported by the driven roller arm.
[5] a front view of the situation from the + Y side sandwiching the recording medium between the driven roller drive roller.
[6] conceptual diagram showing a configuration of a recording apparatus provided with a recording medium conveying apparatus according to the second embodiment.
[Figure 7] a schematic view of the developed conveyance path from the unwind section transport unit constitutes up winding unit to the virtual plane.
[8] a conceptual diagram showing a modification of the structure for moving the driven roller in a predetermined position.
DESCRIPTION OF THE INVENTION
[0019]
　An embodiment embodying the present invention will now be described with reference to the accompanying drawings. The following is an embodiment of the present invention and are not intended to limit the present invention. In the following respective drawings, for ease of explanation, there is a case that has been described in different scale from the actual. In the coordinates appended to the drawings, Z axis direction vertical, + Z direction upward direction, Y axis direction front-rear direction, + Y direction forward direction, X-axis direction is the horizontal direction, + X direction is the left direction, X -Y plane is the horizontal plane. In the following description, the orthogonal, parallel, etc. constant, even when using the representation originally interpreted strictly, they strictly orthogonal, parallel, does not mean a constant only on device performance acceptable It is used as also including degree of error may occur when the degree of error and device fabrication to be.
[0020]
　(Embodiment 1)
　
　FIG. 1 is a perspective view of a recording apparatus 200 provided with a recording medium conveying apparatus according to the first embodiment. 2 is a conceptual diagram showing a configuration of a recording apparatus 200.
　Recording apparatus 200, recording on the recording medium 1 fed by manual insertion from the front of the recording device 200 (printing) is capable inkjet printer, a recording unit 210 for recording on the recording medium 1 was set recorded conveying section 100 as conveying the medium 1 "recording medium transport device", and a control unit 230 for controlling the entire recording apparatus 200. Recording medium 1 is supplied by hand feed the recording apparatus 200 is, for example, a printing paper.
[0021]
　Recording unit 210, and the ejection head 212 for ejecting ink droplets, the ejection head 212 is mounted, transporting (moving surface on the scanning direction (the conveyance section 100 is a recording medium 1 of the recording medium 1 fed by the conveying unit 100 ) and a like carriage 211 which moves in the X-axis direction) intersecting the direction in which the.
　Recording apparatus 200, under the control of the control unit 230, crossing from the ejection head 212 while the carriage 211 is scanned moving and ejecting operation for ejecting ink droplets, the scanning direction in the recording area where the ink droplet from the ejection head 212 is discharged by alternately repeating a transport operation of moving the recording medium 1 in the direction to form a desired image on the recording medium 1 (recording).
[0022]
　Conveying unit 100 includes a plurality of conveying rollers 110, a platen 120, a recording medium guides 130, and the like rear supporters 140, through the recording region of the recording unit 210 from the recording medium guides 130, a recording media guide across the recording area between to the recording standby area on the opposite side of the guide 130 constitute a transport path for the recording medium 1 can be moved back and forth.
[0023]
　Transport roller 110 is constructed, and the like pairs of driven rollers 112 corresponding to the drive roller 111 and drive roller 111. When conveying the recording medium 1, the driven roller 112 nip gives a biasing force in a direction for pressing the recording medium 1 to the drive roller 111 to be paired. Also, when setting the recording medium 1 in manual feed is open at the recording medium guides 130, until the alignment is completed, so that the recording medium 1 to the conveying path is loosely inserted, the driven roller 112 to nip to.
　The platen 120 is disposed in the recording area, for supporting the recording medium 1 in the recording area. Rear supporter 140 is placed in the recording standby area, to support the recording medium before recording.
[0024]
　Conveying rollers 110 of the plurality (two pairs in the example shown in FIG. 2) is controlled by the control unit 230, the recording medium 1 the set is completed to the recording medium guides 130, once to the recording standby area of ​​the rear supporter 140 It conveyed, then, to move the recording medium 1 with the recording operation by moving the recording area on the platen 120. Recording the recording medium is completed 1 is discharged through the recording medium guides 130 again from the recording area by the transport rollers 110. Incidentally, with the discharging operation refers to a direction in which the recording medium 1 passes through the recording medium guides 130 to the discharge direction.
[0025]
　Control unit 230, based on the image data received from the external electronic device or an external storage medium such as a personal computer, controls the recording unit 210 and the conveyance unit 100, as described above, to form an image on the recording medium 1.
[0026]
　In the above configuration, the conventional, remains insufficient alignment recording medium 1 to be set from the recording medium guides 130 (alignment) is or if you set the recording medium 1 in the recording apparatus 200, in the conveying path etc. due to the misalignment, in the conveying path, it was sometimes result by generating a transport wrinkles in the recording medium 1. In contrast, in order to suppress the occurrence of such a situation, in the present embodiment has a configuration for explaining a recording medium conveying device (conveying part 100) below.
[0027]
　
　conveyance unit 100 in the present embodiment, as shown in FIG. 2, in the transport path of the recording medium 1, the transfer roller 110 is provided before and after the platen 120.
　Conveying rollers 110, drives the drive roller 111 in a state in which the roller axis direction and a drive roller 111 and driven roller 112 are parallel to each other and sandwich the recording medium 1 between the drive roller 111 and driven roller 112 conveying the recording medium 1 by. Further, when the driven roller 112 is movably supported from the predetermined position in the roller axis direction, a driven roller 112, without pinching the recording medium 1 between the drive roller 111 is spaced from drive roller 111, driven roller 112 is biased to return to a predetermined position.
　It will be described in detail below.
[0028]
　Figure 3 is a perspective view showing the structure of part of the conveyance section 100.
　FIG. 3 shows the conveying roller 110 on the -Y side of the platen 120, and has a similar structure conveying rollers 110 on the + Y side of the platen 120. Note that the drive mechanism for rotating the conveying roller 110 (drive roller 111), is not shown.
[0029]
　Drive roller 111, across the width direction of the platen 120 (X-axis direction), the recording apparatus 200 extends in length to cover the width of the largest recording medium 1 of interest. The driving roller 111, as the recording medium 1 between the driven roller 112 at the height of the conveying surface of the recording medium 1 the platen 120 is configured is nipped, the rotation axis A-A on the lower side of the platen 120 and in provided so as to rotate.
　Driven roller 112, the upper side of the platen 120, across the width direction of the opposing drive roller 111, a plurality, arranged side by side in series, its rotation axis B-B is supported by the support member 113.
[0030]
　Support member 113 has an arm portion 114 for supporting the rotary shaft B-B of the driven roller 112, the opposite side of the arm portion 114 on the (-Y side in the example of FIG. 3), the support member 113 rotates the rotation and a shaft C-C.
　Support member 113 by turning the rotation axis C-C, or to press a plurality of driven rollers 112 with respect to the driving roller 111, or can moved away from the drive roller 111. Note that the drive mechanism for rotating the support member 113, are not shown.
　Further, the rotation axis A-A, the rotation axis B-B, the rotating shaft C-C are provided in parallel to the X-axis direction, respectively.
[0031]
　Figure 4 is a front view seen from the + Y side manner supported by the driven roller 112 is arm 114.
　Driven roller 112, between the arm portion 114 to be supported, which is movably supported in the roller axis direction (the direction of the rotation axis B-B) in the range of the width Lw. Between the opposite sides of the driven roller 112 and the arm portion 114 of the driven roller 112, a spring member 115 rotating shaft of the driven roller 112 is provided so as to be loosely inserted is disposed. The spring member 115 is a strength enough not to hinder the movement of the driven roller 112, and presses the driven roller 112 in a central position on either side of the arm portion 114 of the driven roller 112. In other words, the driven roller 112, (when the driven roller 112 is in free state) when spaced from drive roller 111 recording medium 1 without pinched between the drive roller 111, driven roller 112 is " It urged by the elastic force of the spring member 115 to return to the center position of each side of the arm portion 114 of the driven roller 112 as a predetermined position ".
[0032]
　5, while the driven roller 112 is supported by the arm portion 114 is pressed against the drive roller 111, a front view of a state in which the recording medium 1 are nipped (nip) from the + Y side between the drive roller 111 it is.
　Driven roller 112 is not only rotated by the rotation of the drive roller 111, the roller axis direction by the stress of the roller axis direction received from the recording medium 1 (the direction of the rotation axis B-B) for clamping between the drive roller 111 it can be moved (in the direction of the rotation axis B-B). Movable range of the driven roller 112 are the narrower than the gap width between the arm portions 114 range (the range of the width Lw of FIG. 4), if the continued to receive movement is required stress exceeding the range of the recording medium 1 , the driven roller 112 has a function to follow the stress is lost.
[0033]
　Therefore, the conveying roller 110, the predetermined position the maximum permissible amount of movement amount of movement from the (center of each side of the arm portion 114 of the driven roller 112) of the driven roller 112 in the (direction of the axis of rotation B-B) roller axis and a detector 116 for detecting that reached the.
　Detector 116, for example, the distance between one end of the roller axis direction of the driven roller 112 (the direction of the rotation axis B-B), and the side wall of the arm portion 114 opposed thereto is, the amount of movement of the driven roller 112 There detects that reached Lmin corresponding to the position reaches the maximum allowable amount of movement. The detection may be a circuit for electrically detecting may be a circuit for detecting optically. The circuit for electrically detecting, for example, upon reaching the Lmin, circuits and for detecting the electrical contact, such as a circuit for sensing a change in distance between the electrodes a change in electrostatic capacitance is considered. The circuit for detecting optically, for example, a the irradiation portion and the light receiving portion, upon reaching the Lmin, is conceivable circuit for detecting the amount of light received that changes by irradiation light or the reflected light is blocked .
[0034]
　Incidentally, the biasing force of the spring member 115 is preferably sufficiently weak to stress received from the recording medium 1.
　Further, the biasing to return the driven roller 112 at a predetermined position, instead of utilizing the elastic force of the spring member 115 may be configured to utilize the magnetic force repel each other.
[0035]
　As described above, according to the recording medium transport device and a recording apparatus according to the present embodiment, it is possible to obtain the following effects.
　Driven roller 112, since it is movably supported from the predetermined position in the roller axis direction (the direction of the rotation axis B-B), the recording medium 1, there in a state of being held between the drive roller 111 and driven roller 112 also, it is easier to move in the roller shaft direction. As a result, for example, even when the wrinkle is worked is likely roller shaft force generated in the recording medium 1, that depending on the force, gradually the recording medium 1 with the transport so as to move is possible, thereby, for example, it can be positional deviation is eliminated and that wrinkles and accumulation occurs. Further, since the driven roller 112, when spaced from the drive roller 111 a recording medium 1 without pinched between the drive roller 111, driven roller 112 is biased to return to a predetermined position, the drive in the initial state for holding the recording medium 1 by the roller 111 and the driven roller 112, driven roller 112, it is possible to move from a predetermined position. For example, by making the center of the movable range of the predetermined position constraint is eliminated with respect to the moving direction.
[0036]
　Further, since the a detection unit 116 for detecting that the amount of movement from the predetermined position of the driven roller 112 in the roller axis direction has reached the maximum allowable moving distance, the maximum allowable amount of movement from the predetermined position of the driven roller 112 it is possible to detect that reaches the movement amount. For example, the driven roller 112 is moved while eliminating the misalignment of the recording medium 1, if the amount of movement is no longer able to overcome the misalignment reaches the maximum allowable amount of movement, appropriate action based on the detection result it is possible to perform.
[0037]
　The recording apparatus 200 can be performed by providing the conveying unit 100 as a "recording medium transport device", the records wrinkles of the recording medium 1 due to misalignment and this has been suppressed.
　In the present embodiment, as shown in FIG. 2, in the transport path of the recording medium 1 has been described in the case where the transport rollers 110 are provided before and after the platen 120, it is not limited to this configuration. For example, the transport roller 110 is one may be (a pair of driven rollers 112 and driven roller 111) and three or more configurations.
[0038]
　(Embodiment 2)
　Next, the recording apparatus 300 provided with a recording medium conveying device and the recording medium conveying apparatus according to the second embodiment will be described. Incidentally, In the description, the same constituent parts in the embodiments described above, using the same reference numerals, and redundant description.
　Figure 6 is a conceptual diagram showing a configuration of a recording apparatus 300 provided with a recording medium conveying apparatus according to the second embodiment.
　Recording apparatus 300 is an ink jet printer for recording an image on the roll paper 301 supplied in a state of being rolled as a "recording medium" (printing).
　The roll paper 301, for example, can be used high-quality paper, cast paper, art paper, coated paper, a synthetic paper. Further, as the recording medium, such not limited to paper, for example, PET (Polyethylene terephthalate), can be used such as a film or fabric long made of a PP (polypropylene).
[0039]
　Recording apparatus 300, recording unit 210, and a like conveying section 320, the control unit 360 as a "recording medium transport device."
　Recording unit 210 has a configuration according to a serial head which reciprocates in the scanning direction (X axis direction) as mentioned above, in a direction crossing a nozzle for ejecting ink to the transport direction, the width direction of the roll paper 301 it may be a configuration of the line head composed of an array of over. Furthermore, it may be a recording apparatus having a recording portion other than the recording head of a so-called ink-jet, such as described above.
[0040]
　Conveying unit 320 is a transport mechanism for moving the roll paper 301 in the conveying direction, a plurality of transport rollers 110, a platen 120, transport path 351 and 352, wound as a "recording medium unwinding unit" detecting section 330, "recording and a like winding section 340 as the medium take-up unit. " Roll paper 301 is supplied from unwind unit 330, conveying path 351 with the recording operation, the recording unit 210 (platen 120), via the conveying path 352, it is housed in the winding section 340.
　The transport unit 320 to backfeed the paper roll 301, by driving the drive roller 111 in reverse, can be moved in the opposite transport direction opposite to the conveying direction the roll paper 301. Back feed, for example, the roll paper 301 is recorded, and if further superposed recording (printing), the case of recording (the adjustment of the recording start position) cueing between jobs (printing), over the entire surface It is performed such as when rewinding the roll paper 301 which recording has been completed unwinding unit 330.
[0041]
　Unwinding unit 330 is a storage portion for storing roll paper 301 before the recording is performed, positioned upstream of the recording unit 210 and the conveying path 351 in the conveying path, and a like unwinding reel 331.
　Unwinding reel 331 is rotated by the unwinding motor is driven and controlled by the control unit 360 (not shown), the transport path 351 which is disposed the roll paper 301 on the downstream side of the unwinding unit 330, to the recording unit 210 Te unwinding.
　Further, unwinding unit 330, by driving the unwinding reel 331 Conversely, it is possible to wind the roll paper 301 is fed backward.
[0042]
　Winding section 340 winding the roll paper 301 after the recording is performed, a storage unit for storing in a state wound into a roll, located downstream of the recording unit 210 and the conveying path 352 in the conveying path and, it has a such as the take-up reel 341.
　Take-up reel 341 includes a rotary shaft rotated by the drive being controlled winding motor (not shown) by the control unit 360, recording unit 210 the rotation axis as the axial center, sent through the transport path 352 rolls the paper 301 is wound.
　Further, the winding unit 340, by driving the take-up reel 341 in the opposite, it is possible to unwind the roll paper 301 is fed backward.
[0043]
　Conveying path conveying unit 320 is configured, the roll paper 301, from unwind unit 330 to convey to the winding section 340 via the recording unit 210, or a path for back feed reverse path, the transport path 351, a platen 120 for supporting the roll paper 301 in the recording area of the recording unit 210, and a like conveying path 352, and the rotary bar member 353.
　Rotating the bar member 353, between the transport path 352 and the winding portion 340, and extends across the width direction of the roll paper 301. The rotation axis of the rotary bar member 353 is fixedly supported on the main body of the recording apparatus 300, the rotary bar member 353 is rotated along with the movement of the roll paper 301 abutting the rotary bar member 353, supports the movement of the roll paper 301 to. The rotation bar member 353 is not necessarily having an axis of rotation, it may be a fixed bar member that supports the roll paper 301 extends over the width direction of the roll paper 301.
[0044]
　Control unit 360, based on the image data received from the external electronic device or an external storage medium such as a personal computer, controls the recording unit 210 and the conveyance unit 320, as described above, to form an image on the roll paper 301.
[0045]
　Figure 7 is a schematic view of the developed conveyance path from the unwind 330 is transported unit 320 constituting up winding unit 340 to the virtual plane.
　In the present embodiment, a predetermined position (center position of each side of the arm portion 114 of the driven roller 112 (see FIG. 4)) of the driven roller 112 concretely as follows the maximum permissible amount of movement which is the maximum allowable amount of movement from It is set to.
　Also in this embodiment, as shown in FIG. 6, in the transport path of the roll paper 301, a description will be given of a case where the conveying roller 110 is provided before and after the platen 120.
　Roll from unwinding unit 330 to a position where the length of the conveyance path of the roll paper 301 to the winding section 340 L1, the roll paper 301 from the unwind 330 is sandwiched between the drive roller 111 and driven roller 112 when the length of the transport path of the paper 301 and L2a (downstream side of the platen 120) and L2b (upstream side of the platen 120), the maximum allowable amount of movement from the predetermined position of the driven roller 112 on the upstream side of the platen 120 Da, and the maximum allowable movement amount Db from a predetermined position of the driven roller 112 on the downstream side of the platen 120, respectively, and calculated by the following expression.
　　Da ≦ 10 mm × L2a /
　　L1 Db ≦ 10 mm × L2b / L1
　that is in accordance with the roll paper 301 which is set as a starting point the unwinding portion 330 away along the conveying path from the starting point, easily shake amount is increased due to the misalignment and set the maximum permissible amount of movement is assumed that.
[0046]
　Above As mentioned, according to the recording medium transport device and a recording apparatus according to the present embodiment, in addition to the effects of the embodiment described above, it is possible to obtain the following effects.
　It can be transported by sandwiching the roll paper 301 supplied in a roll state by the driving roller 111 and driven roller 112, also can be wound. The driven roller 112, since it is movably supported from the predetermined position in the roller axis direction, even when continued conveyance while nipped by the roll paper 301 and the driving roller 111 and driven roller 112, slightly without misalignment of such roll paper 301 is accumulated, it is possible to continue the conveyance while eliminating the deviation. As a result, to generate wrinkles in the roll paper 301 can be prevented.
[0047]
　Also, in the case configured in a straight line when viewed expand conveyance path of the roll paper 301 from the unwind unit 330 to the take-up unit 340 to the virtual plane, a winding displacement in the winding section 340 it can be reduced to 10mm below.
[0048]
　The recording apparatus 300 can be performed by providing the conveying unit 320 as a "recording medium transport device", the records wrinkles of the roll paper 301 due to misalignment or it is suppressed.
[0049]
　(Modification 1)
　In the first embodiment, in order to return the driven roller 112 at a predetermined position (moved), by utilizing the elastic force of the spring member 115, when the driven roller 112 is moved from the predetermined position, the predetermined position biasing force back toward but is configured to be added, but the embodiment is not limited thereto. For example, when nipping the recording medium 1 by the drive roller 111 is not performed urged in a predetermined position direction, in the configuration as biased in a predetermined position direction when driven roller 112 becomes free is performed it may be.
[0050]
　Specifically, for example, the biasing to return the driven roller 112 at a predetermined position, instead of utilizing the elastic force of the spring member 115, a configuration that uses an electromagnetic force repel, the control of the control unit 230 Accordingly, it may be by methods driven roller 112 to generate a biasing force to return the driven roller 112 at a predetermined position by the electromagnetic force only when it becomes free.
[0051]
　Further, in order to return the driven roller 112 at a predetermined position may be configured to utilize a driving force or air, such as a motor (pressure). For example, as shown in FIG. 8, using the cylindrical cam 117 is rotated by the driving force of the motor only when the driven roller 112 becomes free, by driving a motor under the control of the control unit 230, a driven roller 112 or by a method of returning to the predetermined position.
DESCRIPTION OF SYMBOLS
[0052]
　1 ... recording medium, 100 ... transport unit, 110 ... transportation roller, 111 ... driving roller, 112 ... driven roller, 113 ... support member, 114 ... arm, 115 ... spring member, 116 ... detector, 120 ... platen 130 ... recording medium guides, 140 ... rear supporters 200 ... recording device, 210 ... recording unit, 211 ... carriage, 212 ... discharge head, 230 ... controller, 300 ... recorder, 301 ... roll paper, 320 ... conveyor section, 330 ... unwinding unit, 331 ... unwinding reel, 340 ... take-up unit, 341 ... take-up reel, 351, 352 ... transportation path, 360 ... control unit.

claims

A drive roller and a driven roller roller axis direction is parallel to each other,
　conveying the recording medium by driving said drive roller in a state in which the recording medium is sandwiched between the drive roller the driven rollers a recording medium conveying apparatus,
　the driven roller, wherein the roller axis direction is movably supported from the predetermined position,
　the driven roller, the driving roller without pinching the recording medium between the drive roller when spaced apart from, the recording medium transport device, characterized in that the driven roller is moved to the predetermined position in the roller axis direction.
[Requested item 2]
　The driven roller, when in the roller axis direction is moved from the predetermined position, the driven roller, the recording medium conveying apparatus according to claim 1, characterized in that it is biased in a direction to return to the predetermined position .
[Requested item 3]
　Recording as claimed in claim 1 or claim 2, characterized in that the amount of movement from the predetermined position of the driven roller in the roller axis direction and a detecting unit for detecting that reaches the maximum allowable amount of movement medium transport device.
[Requested item 4]
　Said housing a recording medium by unwinding the recording medium recording medium unwinding of the roll state,
　claims 1 to the recording medium winding section for winding said recording medium unwound, characterized in that it comprises a recording medium conveying apparatus according to any one of claims 3.
[Requested item 5]
　D the maximum permissible amount of movement, the length of the conveying path of the recording medium from the recording medium unwinding unit to said recording medium winding unit L1, and the recording medium is the drive roller from the recording medium unwinding unit when the length of the conveying path of the recording medium to a position that is sandwiched between the driven roller L2, and,
　recording as claimed in claim 4, characterized in that the D ≦ 10mm × L2 / L1 medium transport device.
[Requested item 6]
　A recording medium conveying apparatus according to any one of claims 1 to 5,
　the recording apparatus characterized by comprising: a recording unit that performs recording on the recording medium.