JP2017039249A - Recording device and method of moving recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a problem when back-feeding a recording medium.SOLUTION: A printer 100 is equipped with a winding-out portion 30 which winds out a roll sheet 1 carried in a carrying direction, and winds up the roll sheet 1 carried in the reverse carrying direction opposite to the carrying direction; a carrying portion 20 which carries the roll sheet 1 in the carrying direction and the reverse carrying direction; a winding portion 40 which winds up the roll sheet 1 carried in the carrying direction, and winds out the roll paper 1 carried in the reverse carrying direction; and a control portion 60 which controls the winding-out portion 30, the carrying portion 20, and the winding portion 40. The control portion 60 performs drive control assisting the carrying of the roll sheet 1, to the winding portion 40 and the winding-out portion 30, when the carrying portion 20 carries the roll sheet 1 in the reverse carrying direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a recording apparatus and a recording medium moving method.

Conventionally, recording (printing) on a recording medium (roll paper) supplied in a rolled state
A recording device (printer) is used. Such a recording apparatus is often provided with a mechanism for back-feeding a recorded recording medium within the apparatus. For example, Patent Document 1
Includes a medium detecting means for detecting that the end of the recording medium in the feeding direction is located at the recording start position, and the recording medium is moved in a direction opposite to the feeding direction so that the end of the recording medium is at the recording start position. The printer device includes a conveyance control unit that moves until it is detected by the medium detection unit. According to this printer device, the area (printed material) of the recording medium on which the recording has been performed is cut off from the area on which the recording has not been performed, and the recording that has not been performed before the next recording is started. The media can be positioned below the printer head.

JP 2010-23292 A

However, the printer device described in Patent Document 1 has a problem in that it may not be able to effectively back-feed in a usage method in which a recording medium on which recording is performed is not separated. Specifically, when the recording medium is not separated, there is no end portion for detecting the position of the back feed, so that the back feed to a predetermined position cannot be performed. Also,
When the length of the recorded recording medium is long (for example, when a recording unit having a winding unit for winding a recorded recording medium is provided and the recording medium wound up by the winding unit is rewound), backfeed is performed. As a result, there is a problem that the transport roller may slip, and as a result, an accurate back feed amount may not be grasped.

SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following application examples or forms.

Application Example 1 A recording apparatus according to this application example unwinds a recording medium transported in a transport direction, and unwinds a winding unit that winds up the recording medium transported in a reverse transport direction opposite to the transport direction. , A transport unit that transports the recording medium in the transport direction or the reverse transport direction, and a winder that winds the recording medium transported in the transport direction and unwinds the recording medium transported in the reverse transport direction. And a control unit that controls the unwinding unit, the transport unit, and the winding unit, and the control unit, when the transport unit transports the recording medium in the reverse transport direction, Drive control for assisting conveyance of the recording medium is performed on the winding unit and the unwinding unit.

According to the recording apparatus of this application example, the recording medium can be transported in the reverse transport direction (hereinafter also referred to as back feed). The control unit performs drive control for assisting the conveyance of the recording medium to the winding unit and the unwinding unit when the recording medium is back-fed. That is, the winding unit and the unwinding unit generate torque in a direction that assists the back feed of the transport unit, so that the recording medium can be back fed more smoothly. As a result, for example, it is possible to perform back feed with high accuracy without causing slippage or the like on the transport roller provided in the transport unit.

Application Example 2 In the recording apparatus according to the application example, when the transport unit transports the recording medium in the reverse transport direction, the control unit, between the transport unit and the unwinding unit, Driving the unwinding unit with a driving torque that applies a predetermined tension to the recording medium, and driving the winding unit with a driving torque lower than the driving torque at which the winding unit starts unwinding of the recording medium; Features.

According to this application example, in the above recording apparatus, when the transport unit back feeds the recording medium, the control unit applies a predetermined amount to the recording medium between the transport unit and the unwinding unit that winds the recording medium. The unwinding part is driven with a driving torque to which tension is applied. For this reason, the occurrence of sagging or slack in the recording medium wound around the unwinding portion is suppressed.
Further, the control unit drives the winding unit with a driving torque that is lower than a driving torque at which the winding unit starts to unwind the recording medium when the transport unit back-feeds the recording medium. For this reason, the take-up unit does not self-run and unwinds the recording medium, and the recording medium can be unwound only by applying a slight tension to the recording medium.
As a result, the back feed of the recording medium can be performed more smoothly.

Application Example 3 In the recording apparatus according to the application example, when the winding torque at which the winding unit starts unwinding the recording medium is tra1, and the driving torque for driving the winding unit is tra2. , Tra1 × 0.3 ≦ tra2 ≦ tra1 × 0.9.

According to this application example, the back-feed is assisted by at least 30% or more of the torque assist of the driving torque tra1 at which the winding unit starts to unwind the recording medium, so the load on the winding unit is increased. Even in this case, the back-feed assist is suppressed from becoming insufficient. Further, since the torque assist is performed with a small torque (a torque having a margin of at least 10% or more) compared to the torque that the winding unit self-runs and unwinds the recording medium, the load on the winding unit is small. Even in such a case, due to mechanical variation of the configuration of the winding unit, it is possible to prevent the winding unit from self-running and rotating and unwinding the recording medium. As a result, the back feed of the recording medium can be performed more smoothly.

Application Example 4 A recording medium moving method according to this application example is a winding method for unwinding a recording medium transported in a transport direction and winding the recording medium transported in a reverse transport direction opposite to the transport direction. A take-out unit, a transport unit that transports the recording medium in the transport direction or the reverse transport direction, and the recording medium transported in the transport direction, and winds the recording medium transported in the reverse transport direction And a winding unit for taking out the recording medium, wherein the transport unit transports the recording medium in the reverse transport direction with respect to the winding unit and the unwinding unit. Further, drive control for assisting conveyance of the recording medium is performed.

According to the moving method of the recording medium of this application example, when the recording medium is back-fed, drive control for assisting the conveyance (movement) of the recording medium is performed on the winding unit and the unwinding unit. That means
Since the winding unit and the unwinding unit generate torque in a direction that assists the back feed of the transport unit, the back feed of the recording medium can be performed more smoothly. As a result, for example, it is possible to perform back feed with high accuracy without causing slippage or the like on the transport roller provided in the transport unit.

Application Example 5 In the recording medium moving method according to the application example described above, when the transport unit transports the recording medium in the reverse transport direction, the recording is performed between the transport unit and the unwinding unit. The unwinding unit is driven with a driving torque to which a predetermined tension is applied to the medium, and the winding unit is driven with a driving torque lower than the driving torque at which the winding unit starts unwinding of the recording medium. To do.

According to the moving method of the recording medium of the application example, when the transport unit back-feeds the recording medium, the unwinding unit is driven with a driving torque that applies a predetermined tension to the recording medium between the transporting unit and the unwinding unit. Drive. For this reason, the occurrence of sagging or slack in the recording medium wound around the unwinding portion is suppressed.
Further, when the transport unit back feeds the recording medium, the winding unit drives the winding unit with a driving torque lower than the driving torque at which the winding unit starts to unwind the recording medium. For this reason, the take-up unit does not self-run and unwinds the recording medium, and the recording medium can be unwound only by applying a slight tension to the recording medium.
As a result, the back feed of the recording medium can be performed more smoothly.

1 is a schematic side view of a recording apparatus according to a first embodiment. 1 is a block diagram of a recording apparatus according to a first embodiment. (A) to (c) Time chart when winding the recording medium (A) to (d) Time chart at the time of back feed of the recording medium

DESCRIPTION OF EMBODIMENTS Embodiments embodying the present invention will be described below with reference to the drawings. The following is one embodiment of the present invention and does not limit the present invention. In the following drawings, the scale may be different from the actual scale for easy understanding.

(Embodiment 1)
<Recording device (printer)>
FIG. 1 is a schematic side view of a printer 100 as a “recording apparatus” according to the first embodiment. FIG. 2 is a block diagram of the printer 100.
The printer 100 is an ink jet printer that records (prints) an image on a roll paper 1 that is supplied in a rolled state as a “recording medium”.
The printer 100 includes a recording unit 10, a conveyance unit 20, an unwinding unit 30, a winding unit 40, and a conveyance path 50.
The control unit 60 and the like are provided.

The roll paper 1 is supplied from the unwinding unit 30, and the recording unit 1 is conveyed by the conveyance path 50 along with the recording operation.
0 is stored in the winding unit 40.
As the roll paper 1, for example, high-quality paper, cast paper, art paper, coated paper, synthetic paper, or a film made of PET (Polyethylene terephthalate), PP (polypropylene), or the like can be used.

The recording unit 10 includes a recording head 11, a carriage 12, a guide shaft 13, and the like. The recording head 11 is an ink jet head provided with a plurality of nozzles that eject ink. The guide shaft 13 extends in the scanning direction that intersects the transport direction in which the roll paper 1 moves. The carriage 12 carries the recording head 11 and reciprocates (scans) along the guide shaft 13 by a carriage motor 14 (see FIG. 2) driven and controlled by the controller 60.

The control unit 60 alternately repeats the operation of ejecting ink droplets from the recording head 11 while moving the carriage 12 in the scanning direction and the transporting operation of moving the roll paper 1 in the transporting direction by the transporting unit 20. A desired image is formed (recorded) on the paper 1. That is, the transport unit 20 intermittently transports the roll paper 1 through repeated transport operations when recording on the roll paper 1.

The recording unit 10 is configured by a serial head that reciprocates in the scanning direction as described above. However, the nozzle that ejects ink crosses the conveyance direction in the width direction of the roll paper 1. An arrangement of line heads arranged side by side may be used. Furthermore, a recording apparatus having a recording unit other than the so-called ink jet recording head as described above may be used.

The transport unit 20 is a transport mechanism that moves the roll paper 1 in the transport direction in the recording unit 10, and includes a drive roller 21 with a nip roller. Drive roller 21
By driving the drive roller 21 with the roll paper 1 sandwiched between the nip roller and the nip roller, the roll paper 1 is conveyed at a speed corresponding to the peripheral speed of the drive roller 21. That is, when there is no expansion / contraction of the roll paper 1 or slippage between the drive roller 21 and the roll paper 1, the peripheral speed of the drive roller 21 is equal to the conveyance speed of the roll paper 1.
The driving roller 21 is driven by a transport motor 22 (see FIG. 2) that is driven and controlled by the control unit 60. The drive roller 21 is provided with a rotary encoder.
In addition, the conveyance part 20 is not limited to the structure by these rollers, For example,
You may comprise by a conveyance belt etc.

Further, the transport unit 20 moves the roll paper 1 in the reverse transport direction opposite to the transport direction by driving the drive roller 21 (transport motor 22) in reverse to feed back the roll paper 1. Can do. Backfeed is performed over the entire surface, for example, when further recording (printing) is performed on a recorded recording medium, or when cueing (adjustment of the recording start position) between recording (printing) jobs is performed. This is performed when the roll paper 1 that has been completed is rewound to the unwinding unit 30.

The unwinding unit 30 is a storage unit that stores the roll paper 1 before recording. The unwinding unit 30 is located on the upstream side of the recording unit 10 in the conveyance path 50 and includes an unwinding reel 31 and the like.
The unwinding reel 31 is driven and controlled by the control unit 60. The unwinding motor 32 (see FIG. 2).
The roll paper 1 is unwound toward the recording unit 10 disposed on the downstream side of the unwinding unit 30.
Moreover, the unwinding part 30 can wind up the roll paper 1 fed back by driving the unwinding reel 31 (unwinding motor 32) in reverse.

The winding unit 40 is a storage unit that winds the roll paper 1 after recording and stores the rolled paper 1 in a roll shape. The winding unit 40 is located on the downstream side of the recording unit 10 in the conveyance path 50 and is wound. Reel 4
1 and so on.
The take-up reel 41 is driven and controlled by the control unit 60 (see FIG. 2).
The roll paper 1 that has been rotated through the recording unit 10 is wound up around the rotation axis. A rotary encoder is provided on the rotating shaft.
The take-up unit 40 can unwind the roll paper 1 to be back-fed by driving the take-up reel 41 (winding motor 42) in the reverse direction.

The conveyance path 50 is a conveyance path that conveys the roll paper 1 from the unwinding section 30 to the winding section 40 via the recording section 10 or back-feeds in the reverse path. Medium support portion 51 including a platen that supports roll paper 1 and rotating bar member 5
2 or the like.
The rotating bar member 52 includes an end on the downstream side of the conveyance path formed by the medium support unit 51 and the winding unit 40.
Between the roll paper 1 and the width of the roll paper 1. The rotation axis of the rotation bar member 52 is fixedly supported by the main body of the printer 100, and the rotation bar member 52 rotates with the movement of the roll paper 1 that contacts the rotation bar member 52, and supports the movement of the roll paper 1. . The rotating bar member 52 does not necessarily have a rotating shaft, and may be a fixed bar member that extends in the width direction of the roll paper 1 and supports the roll paper 1.

As shown in FIG. 2, the control unit 60 includes an input / output unit 61, a CPU 62, a memory 63, a timer 64, a head driving unit 65, a motor driving unit 66, a system bus 67, and the like, and performs centralized control of the entire printer 100. .
The input / output unit 61 includes an external device (for example, a personal computer PC) and the printer 10.
Data is transmitted to and received from 0.
The CPU 62 is an arithmetic processing unit for controlling the entire printer 100, and includes an input / output unit 61, a memory 63, a timer 64, a head driving unit 65, and the like via a system bus 67.
The motor drive unit 66 is connected.
The memory 63 is an area in which a program for operating the CPU 62 is stored and necessary information is recorded. The memory 63 includes storage elements such as a RAM, a ROM, and a flash memory.
The CPU 62 controls the head driving unit 65 and the motor driving unit 66 in accordance with a program stored in the memory 63 and a recording job (printing instruction) received from an external device.

The control unit 60 determines the amount of movement of the roll paper 1 in the conveyance unit 20, the conveyance speed, and the movement of the roll paper 1 in the winding unit 40 from the reading values of the rotary encoders provided in the conveyance unit 20 and the winding unit 40. The amount, winding speed, etc. can be recognized. In addition,
These moving amounts and speeds may be measured by providing the transport unit 20 and the winding unit 40 with a laser Doppler velocimeter or the like.

When the roll unit 1 winds the roll paper 1 in synchronization with the transport operation of the transport unit 20, the control unit 60 sets the torque limit threshold of the wind unit 40 based on the speed at which the roll paper 1 is transported. Switch.
Hereinafter, specifically, when the roll paper 1 is taken up, the drive timing of the transport unit 20 (drive roller 21) and the take-up unit 40 (take-up reel 41), the threshold of the torque limit, the torque of the take-up unit 40, etc. Will be described.

<Roll paper winding method>
3A to 3C are time charts when the roll paper 1 is moved in the transport direction and wound around the winding unit 40. FIG. FIG. 3A shows the conveyance speed of the conveyance unit 20, and FIG. 3B shows the winding unit 40.
FIG. 3C shows the change over time in the torque limit threshold value of the take-up reel 41.
As described above, the transport unit 20 intermittently transports the roll paper 1 through repeated transport operations when recording on the roll paper 1. FIGS. 3A to 3C show 1 of this repeated transport operation.
It is a time chart in the conveyance operation of batch.
When there is no expansion / contraction of the roll paper 1 or slippage between the rotary shaft of the take-up reel 41 and the roll paper 1, the peripheral speed of the roll paper 1 becomes equal to the winding speed of the roll paper 1. Further, when the roll paper 1 is not expanded or contracted, the winding speed of the roll paper 1 becomes equal to the transport speed of the roll paper 1 in the transport unit 20.

First, when the control unit 60 starts (or resumes) conveyance and winding in repeated conveyance operations, the control roller 60 drives the driving roller so that the acceleration drive P1 of the conveyance unit 20 and the acceleration drive R1 of the winding unit 40 are synchronized. 21 and the take-up reel 41 are driven. The torque limit threshold value of the take-up reel 41 at this time is set to tr1 by the control unit 60.

The drive of the take-up reel 41 is controlled by the controller 60 at a predetermined upper limit torque (torque limit set by a torque limit threshold) and a predetermined upper limit speed. For this reason, when the torque of the take-up reel 41 has reached the upper limit torque, it is driven in the upper limit torque state, but when the torque of the take-up reel 41 has not reached the upper limit torque, the upper limit speed is set as the upper limit. Accelerated.

Further, the control unit 60 is driven so that the roll paper 1 is transported and wound in a state in which the tension in the direction along the transport direction is applied to the roll paper 1. Specifically, the driving roller 2
1, so that the winding speed of the roll paper 1 by the take-up reel 41 is higher than the transport speed of the roll paper 1 by the roll 1, and the winding section 40 (winding motor 22).
) Is controlling.

Next, when the transport speed reaches a predetermined speed, the control unit 60 changes the drive mode of the transport unit 20 from the acceleration drive P1 to the constant speed drive P2, and the drive mode of the winding unit 40 from the acceleration drive R1 to the constant speed drive. Set to R2. At the same time, the torque limit threshold value of the take-up reel 41 is changed from tr1 to tr2.
Switch to.

Next, in order to complete predetermined conveyance, the control unit 60 changes the drive mode of the conveyance unit 20 from the constant speed drive P2 to the deceleration drive P3, and changes the drive mode of the winding unit 40 from the constant speed drive R2 to the deceleration drive R3.
To. At the same time, the torque limit threshold value of the take-up reel 41 is switched from tr2 to tr3.

Next, the control unit 60 stops driving the transport unit 20 and the winding unit 40, and at the same time, increases the torque limit threshold value of the winding reel 41 from tr3 to tr4 and then decreases to tr5.
By raising the torque limit threshold value to tr4 once, if the roll paper 1 of the winding unit 40 is loosened, it can be tightened. The torque limit threshold is t
By maintaining r5, loosening of the roll paper 1 can be prevented. That is, torque is continuously applied to the take-up motor 42 even when stopped.

<Calculation of torque limit threshold>
Here, the threshold tr of the torque limit is obtained by the following method with respect to the tension F that causes the torque limit to function (that is, the tension F at the upper limit torque).
First, in the initial state, the rotational load of the take-up reel 41 (specifically, the current value required for the rotation of the take-up reel 41) is measured at two kinds of rotational speeds, low speed and high speed, and provided on the take-up reel 41. The relationship between the rotation speed and the rotation load with respect to the encoder cycle is obtained.
The low-speed rotation speed measured here is x1, and the high-speed rotation speed is x2.
Next, the average rotational load in PID control (Proportional-Integral-Derivative Controller) is also calculated corresponding to the two types of rotational speeds of the take-up reel 41, low speed and high speed.
The low-speed average rotational load measured here is y3, and the high-speed average rotational load is y4. Further, when the roll outer diameter of the rolled paper 1 is D and the rotation speed of the take-up reel 41 is X,
The torque limit threshold tr is obtained by the following equation 1. Here, K is a coefficient for converting the torque corresponding to the tension F into a torque limit.
Note that when the drive control of the take-up reel 41 is performed by voltage control, the rotational load may be a voltage value.

The threshold tr of the torque limit is calculated at any time with a short cycle of, for example, 1 μsec to 1 msec.
As the torque limit threshold value tr, the value calculated immediately before when the control unit 60 determines to switch the torque limit threshold value is used. That is, the control unit 60 changes the speed of the transport unit 20 from acceleration to constant speed, from constant speed to deceleration, from deceleration to stop so that the driving state of P1, P2, and P3 shown in FIG. The torque limit threshold tr is calculated using the torque limit threshold tr calculated when the speed is closest to the timing of changing the speed, such as the degree of acceleration or deceleration.

<Back feed of roll paper>
Next, a back feed mechanism for the roll paper 1 that characterizes the present embodiment and a back feed method for the roll paper 1 as a “recording medium moving method” will be described. Specifically, the drive timing of the transport unit 20 (drive roller 21), the unwinding unit 30 (unwinding reel 31), and the winding unit 40 (winding reel 41) when the roll paper 1 is back-feeded, The threshold of the torque limit of the output part 30, the assist torque of the winding part 40, etc. are demonstrated.

4A to 4D are time charts when the roll paper 1 is back-fed. FIG. 4A shows the conveyance speed of the conveyance unit 20 during back feed, and FIG. 4B shows the unwinding unit 30.
4 (c) shows a torque limit threshold value when winding with the unwinding reel 31,
FIG. 4 (d) shows changes over time in the assist torque when unwinding with the take-up reel 41.

When the roll paper 1 is back-feeded, the control unit 60 performs drive control for generating torque in the direction of assisting the conveyance of the roll paper 1 with respect to the unwinding unit 30 and the winding unit 40. Here, the drive control with respect to the unwinding unit 30 and the winding unit 40 is specifically the drive control with respect to the unwinding motor 32 and the winding motor 42 performed by the control unit 60. It is to control the size and direction.
First, when starting the back feed, the control unit 60 drives the drive roller 21 and the unwinding reel 31 so that the acceleration drive P1b of the transport unit 20 and the acceleration drive R1b of the unwinding unit 30 are synchronized. The threshold value of the torque limit of the unwinding reel 31 at this time is determined by the control unit 60 as tr1.
b.

The control unit 60 is driven so that the roll paper 1 is back-fed and wound in a state where a predetermined tension in the direction along the reverse conveyance direction is applied to the roll paper 1. Specifically, the conveying unit 20 and the unwinding unit 30 are controlled so that the winding speed of the roll paper 1 by the unwinding reel 31 is higher than the conveying speed of the roll paper 1 by the driving roller 21.

In addition, the control unit 60 includes a driving torque tra that causes the winding unit 40 to start unwinding the roll paper 1.
The winding unit 40 is driven with a driving torque tra2 less than 1. The driving torque tra1 is obtained from the rotational load when the rotation is started when the winding unit 40 is unloaded (the roll paper 1 is not wound). The driving torque tra2 of the winding unit 40 for assisting the backfeed is set to a torque smaller than the driving torque tra1, and the winding unit 40 is driven before the conveying unit 20 and the unwinding unit 30 start driving for backfeeding. The torque is set so that it does not start to rotate by itself. In the example shown in FIG. 4D, tra2 = tra1 × 0.8.
That is, the assist of the winding unit 40 in the present embodiment is to give a torque smaller than the rotational load. Therefore, even if only the assist torque is applied, the winding unit 40 does not roll the roll paper 1.
Do not start unwinding.

The driving torque tra2 of the winding unit 40 is tra1 × 0.3 ≦ tra2 ≦ tra1 ×.
A range of 0.9 is preferred. When tra1 × 0.3> tra2, the assist torque may be insufficient when the load of the winding unit 40 (the amount of the rolled roll paper 1) is large. Also, tra2> tra1 × 0.9, when the load of the winding unit 40 is small due to mechanical variations in the configuration of the winding unit 40, the winding reel 41 is self-propelled and rotates,
This is because the roll paper 1 may be unwound.

Next, when the conveyance speed of the back feed reaches a predetermined speed, the control unit 60 conveys the conveyance unit 20.
The driving mode is changed from the acceleration driving P1b to the constant speed driving P2b, and the driving mode of the unwinding section 30 is changed from the acceleration driving R1b to the constant speed driving R2b. At the same time, the torque limit threshold value of the unwinding reel 31 is switched from tr1b to tr2b.
The threshold value of the torque limit of the unwinding reel 31 is not necessarily limited when the tension applied to the roll paper 1 is maintained within a predetermined tension range between the transport unit 20 and the unwinding unit 30.
There is no need to switch from tr1b to tr2b.

Next, when the back feed of the roll paper 1 reaches a predetermined amount, or when the winding to the unwinding unit 30 is completed, the control unit 60 completes the predetermined back feed in order to complete the predetermined back feed. The driving mode is changed from the constant speed drive P2b to the deceleration drive P3b, and the drive mode of the unwinding section 30 is changed from the constant speed drive R2b to the deceleration drive R3b. At the same time, the torque limit threshold value of the unwinding reel 31 is switched from tr2b to tr3b.
The threshold value of the torque limit of the unwinding reel 31 is not necessarily limited when the tension applied to the roll paper 1 is maintained within a predetermined tension range between the transport unit 20 and the unwinding unit 30.
There is no need to switch from tr2b to tr3b.

Further, the control unit 60 stops driving the winding unit 40. That is, the assist with respect to the back feed is stopped, and the mode is shifted to the mode in which the natural stop is performed.
Next, the control unit 60 stops driving the transport unit 20 and the unwinding unit 30.
Thus, the back feed of the roll paper 1 is completed.

As described above, according to the recording apparatus and the recording medium moving method according to the present embodiment, the following effects can be obtained.
When the control unit 60 conveys (back feeds) the roll paper 1 in the reverse conveyance direction, the winding unit 4
Drive control for generating torque in a direction that assists the conveyance of the roll paper 1 is performed on the 0 and the unwinding unit 30. Since the winding unit 40 and the unwinding unit 30 generate torque in a direction that assists the back feed of the transport unit 20, the roll paper 1 can be back fed more smoothly. As a result, for example, it is possible to perform back feed with high accuracy without causing slippage or the like on the transport roller included in the transport unit 20.

In addition, the control unit 60 controls the conveyance unit 20 when the conveyance unit 20 back-feeds the roll paper 1.
And the unwinding unit 30 for winding the roll paper 1, the unwinding unit 30 is driven with a driving torque that applies a predetermined tension to the roll paper 1. Therefore, the occurrence of sagging or looseness on the roll paper 1 wound around the unwinding unit 30 is suppressed.
The control unit 60 also includes a winding unit 40 when the transport unit 20 back-feeds the roll paper 1.
Drives the winding unit 40 with a driving torque lower than the driving torque for starting unwinding of the roll paper 1. Therefore, the winding unit 40 does not self-run to unwind the roll paper 1, and the roll paper 1 can be unwound only by applying a slight tension to the roll paper 1.
As a result, the back feed of the roll paper 1 can be performed more smoothly.

Further, the back feed is assisted by the torque assist of at least 30% or more of the driving torque tra1 at which the winding unit 40 starts to unwind the roll paper 1, and the winding unit 4
For a situation where 0 runs by itself and unrolls the roll paper 1, torque assist is performed with a margin of at least 10%. As a result, when the load on the winding unit 40 (the amount of the rolled paper 1) is large, the assist function becomes insufficient, and when the load on the winding unit 40 is small, the winding reel 41 is The self-running rotation of the roll paper 1 is suppressed, and the roll paper 1 can be fed back more smoothly.

DESCRIPTION OF SYMBOLS 1 ... Roll paper, 10 ... Recording part, 11 ... Recording head, 12 ... Carriage, 13 ... Guide shaft, 14 ... Carriage motor, 20 ... Conveyance part, 21 ... Drive roller, 22 ... Conveyance motor, 30 ... Unwinding part, DESCRIPTION OF SYMBOLS 31 ... Unwinding reel, 32 ... Unwinding motor, 40 ... Winding part, 41 ... Winding reel, 42 ... Winding motor, 50 ... Conveyance path, 51 ... Medium support part, 52 ... Rotation bar member, 6
0 ... control unit 61 ... input / output unit 62 ... CPU 63 ... memory 64 ... timer 65 ...
Head drive unit, 66... Motor drive unit, 67... System bus, 100.

Claims (5)

An unwinding unit for unwinding the recording medium transported in the transport direction and winding the recording medium transported in the reverse transport direction opposite to the transport direction;
A transport unit that transports the recording medium in the transport direction or the reverse transport direction;
A winding unit that winds up the recording medium transported in the transport direction and unwinds the recording medium transported in the reverse transport direction;
A control unit for controlling the unwinding unit, the conveying unit, and the winding unit,
The control unit performs drive control for assisting conveyance of the recording medium to the winding unit and the unwinding unit when the conveyance unit conveys the recording medium in the reverse conveyance direction. A recording device. The control unit, when the transport unit transports the recording medium in the reverse transport direction,
A driving torque for driving the unwinding unit with a driving torque that applies a predetermined tension to the recording medium between the conveying unit and the unwinding unit, and for the winding unit to start unwinding of the recording medium. The recording apparatus according to claim 1, wherein the winding unit is driven with a lower driving torque. The driving torque at which the winding unit starts unwinding the recording medium is referred to as tra1,
When the driving torque for driving the winding unit is tra2,
tra1 × 0.3 ≦ tra2 ≦ tra1 × 0.9
The recording apparatus according to claim 2, wherein: An unwinding unit for unwinding the recording medium transported in the transport direction and winding the recording medium transported in the reverse transport direction opposite to the transport direction;
A transport unit that transports the recording medium in the transport direction or the reverse transport direction;
A winding unit that winds the recording medium transported in the transport direction and unwinds the recording medium transported in the reverse transport direction, and a method for moving the recording medium in a recording apparatus comprising:
When the transport unit transports the recording medium in the reverse transport direction, drive control for assisting transport of the recording medium is performed on the winding unit and the unwinding unit. Moving method. When the transport unit transports the recording medium in the reverse transport direction, the unwinding unit is driven with a driving torque that applies a predetermined tension to the recording medium between the transport unit and the unwinding unit. ,
5. The method for moving a recording medium according to claim 4, wherein the winding unit drives the winding unit with a driving torque that is lower than a driving torque at which the winding unit starts to unwind the recording medium.

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