JP2011189748A - Control method of roll paper printer and roll paper printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To propose a roll paper printer in which an excessive paper feeding load does not act on a paper feeding roller even in case that a paper feeding speed is accelerated. <P>SOLUTION: In a roll paper storage unit 11 of the roll paper printer 1, a send-out roller 81 attached to roll paper 12 and a send-out motor 82 for rotatably driving this roller 81 are disposed. The roll paper 12 is rotated by the send-out roller 81 to send out the recording paper 12a so that the slack Δ corresponding to a paper feeding amount is generated on the recording paper part at this side of a rear-side paper feeding roller 34 during the time from the paper feeding ending time point T5 to the next paper feeding starting time point T2. Since the inertial load of the roll paper 12 does not act on the rear-side paper feeding roller 34 by the slack Δ at the paper feeding time (time points T2 to T5), the paper feeding load can be reduced, and the decrease of the paper feeding accuracy can be prevented. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a roll paper printer that performs printing on a long recording paper fed out from roll paper stored in a rollable state in a roll paper storage unit. More specifically, the present invention relates to a roll paper feeding control method and a roll paper feeding mechanism of a roll paper printer that can reduce the paper feeding load acting on the paper feeding roller and perform paper feeding with high accuracy.

  In a roll paper printer that issues a receipt or the like, a roll paper having a configuration in which a long recording paper is wound in a roll shape is used as a recording medium. The roll paper is stored in the roll paper storage unit in a rollable state, the recording paper is drawn from the roll paper by the paper feed roller, and printing is performed by the print head at the printing position. In general, paper feeding by a paper feeding roller and printing by a print head are alternately repeated, and printing is performed at a predetermined pitch along the paper feeding direction.

  The roll paper is placed in a rollable state on the bottom surface of the roll paper storage unit. When the recording paper is pulled in the transport direction by the paper feeding roller, the roll paper is rotated around its central axis in the roll paper storage unit and fed out. It is necessary to feed the recording paper by rotating the roll paper against the inertial load of the roll paper and the frictional force between the roll paper and the bottom surface of the roll paper storage unit. The recording paper is pressed against the paper feeding roller by the paper pressing roller with a predetermined pressing force so that the recording paper can be fed out without slipping even under such a paper feeding load.

  Patent Document 1 is a prior art document for the purpose of feeding roll paper without being affected by increase or decrease in paper feed load. Here, in a large-sized printer in which roll paper is rotatably supported on a supply reel, in order to feed the roll paper accurately and smoothly, the roll paper is pressed with a predetermined elastic force and held in a bent state. Buffer means for relaxing the tension acting at the initial stage of feeding is disclosed. Patent Document 2 discloses a roll paper feeding device for accurately feeding recording paper without being affected by external fluctuation factors such as variation in the diameter of the feeding roller and roll diameter. ing.

JP 2003-192202 A JP 7-33295 A

  Here, when the paper feed speed is increased, the paper feed load acting on the paper feed roller is increased accordingly. In order to convey the recording paper without slipping, it is necessary to press the paper pressing roller against the paper feeding roller with a larger pressing force. When the pressing force is increased, the load torque of the paper feed motor for rotationally driving the paper feed roller increases. Therefore, it is necessary to use a paper feed motor having a high torque capacity. In addition, since a large pressing force acts, the durability of the paper feeding roller and the paper pressing roller may be reduced.

  Next, in the roll paper printer, the printing operation and the paper feeding operation are alternately performed as described above. That is, the paper feeding operation by the paper feeding roller is performed intermittently. When the roll paper is not supported in a rotatable state around its core by a spindle such as a feeding reel, and is simply placed in a rollable state on the bottom surface of the roll paper storage unit, When the paper feed speed is increased, the roll paper cannot be rotated following the recording paper pulling operation by the paper feed roller, and the roll paper may rise as a whole from the bottom surface of the roll paper storage unit.

  When the raised roll paper falls again to the bottom surface of the roll paper storage unit, the weight of the roll paper acts as a pulling force that pulls the recording paper fed from the roll paper in the direction opposite to the transport direction. If the fall of the roll paper overlaps with the next drawing operation (paper feeding operation) of the recording paper by the paper feeding roller, an excessive paper feeding load is temporarily applied to the paper feeding roller, and the paper feeding roller and the recording paper Slipping occurs between the two, and an accurate amount of paper cannot be fed.

  In view of such problems, an object of the present invention is to propose a roll paper printer including a roll paper feed mechanism that can reduce a paper feed load acting on a paper feed roller.

  Another object of the present invention is to propose a roll paper feed control method capable of reducing a paper feed load acting on a paper feed roller in a roll paper printer.

In order to solve the above problems, the roll paper printer of the present invention is
A roll paper storage section for storing the roll paper in a rollable state;
A feeding roller disposed at a position capable of contacting the outer peripheral surface of the roll paper stored in the roll paper storage unit;
A print head;
A paper feed roller for conveying the long recording paper fed from the roll paper in the roll paper storage unit via the print position by the print head;
A paper feed motor for rotationally driving the paper feed roller;
It has a feeding motor for rotationally driving the feeding roller.

  In the roll paper storage unit of the roll paper printer of the present invention, a feed roller is disposed at a position where it can contact the outer peripheral surface of the roll paper stored therein, and this feed roller is driven to rotate by a dedicated feed motor. The When the feeding roller rotates, the roll paper rotates about its central axis. Therefore, for example, when paper is fed by the paper feed roller, the feed roller is synchronously driven to rotate, and the roll paper is rotated in the recording paper feed direction, so that the recording paper is fed from the roll paper independently of the paper feed motor. You can pay out.

  By rotating the roll paper and feeding the recording paper therefrom, the paper feed load acting on the paper feed roller is reduced. As a result, even when the paper feed speed is increased, the paper feed force can be reduced, and the pressing force by the paper press roller can be reduced. Therefore, the torque of the paper feed motor can be reduced, and the paper feed roller and the paper presser roller can be reduced. Durability is also improved. Furthermore, since the roll paper does not lift from the bottom surface of the roll paper storage unit during paper feeding, it is possible to avoid the adverse effect that the paper feeding accuracy is reduced due to an excessive paper feeding load.

  Here, the roll paper printer of the present invention uses one or both of the period of the printing operation by the print head and the period of the paper feeding operation by the paper feeding roller performed following the printing operation. And a control section for rotating the feeding roller.

  For example, when the feeding roller is rotated by the feeding motor and the roll paper is rotated in the recording paper feeding direction using the period of the printing operation, the portion of the recording paper that is fed from the roll paper to the paper feeding roller Gradually loosens. Therefore, when the paper feed roller is rotated at the time of the next paper feed, the recording paper is loosened, so that the inertia load of the roll paper does not act on the paper feed roller, and the paper feed starts smoothly. . Further, the paper feeding load during the paper feeding operation is also reduced.

  Here, when the slack of the recording paper is larger than the paper feed amount, the slack of the recording paper gradually increases, causing a problem such as a paper jam between the roll paper and the paper feed roller. On the other hand, when the slack of the recording paper is smaller than the paper feed amount, the slack of the recording paper disappears during the paper feeding operation, and thereafter, the paper feeding load of the paper feeding roller increases.

  The control unit of the roll paper printer of the present invention is characterized in that the feed roller is rotated so that the roll paper is rotated in the recording paper feed direction by an amount corresponding to a paper feed amount necessary for the paper feed operation. Yes. In this way, if the roll paper is rotated by the feed roller corresponding to the paper feed amount, the slack of the recording paper from the roll paper to the paper feed roller is eliminated every paper feed operation. Therefore, problems such as a paper jam and an increase in paper feed load do not occur.

  Next, the present invention is a roll paper feeding control method of the roll paper printer having the above-described configuration, in which a period of a printing operation by the print head and a paper feeding operation by the paper feeding roller performed following the printing operation. The feeding roller is rotated using one or both of the periods.

  In the roll paper feed control method of the present invention, the feed roller is rotated so that the roll paper is rotated in the recording paper feed direction by an amount corresponding to the paper feed amount necessary for the paper feed operation. Yes.

  On the other hand, the present invention is a roll paper feeding mechanism for feeding a long recording paper from a roll paper stored in a rollable state in a roll paper storage unit of a roll paper printer, the roll paper storage A feeding roller disposed at a position capable of contacting the outer peripheral surface of the roll paper stored in the section, and a long recording paper fed from the roll paper in the roll paper storage section through the printing position. Independently of the paper feed roller for carrying, it has a feeding motor that rotationally drives the feeding roller.

  In the present invention, a feed roller is disposed in the roll paper storage unit at a position where the roll paper can be brought into contact with the outer peripheral surface of the roll paper stored therein, and this feed roller is rotationally driven by a dedicated feed motor. Since there is no need to rotate the roll paper by the paper feed roller and feed out the recording paper, the paper feed load of the paper feed roller can be greatly reduced and the roll paper can be prevented from being lifted. In particular, when the paper feed speed of the roll paper printer is increased, the effect of the present invention is remarkable.

1 is an external perspective view of a roll paper printer to which the present invention is applied. FIG. 2 is an external perspective view of a roll paper printer with an open / close lid open. It is a perspective view showing a printer mechanism part of a roll paper printer. It is a schematic longitudinal cross-sectional view of a printer mechanism part. It is explanatory drawing which shows a roll paper delivery mechanism. It is a schematic block diagram of a control system of the roll paper printer. FIG. 10 is an operation explanatory diagram illustrating a relationship among operations of printing, paper feeding, and roll paper feeding.

  Embodiments of a roll paper printer to which the present invention is applied will be described below with reference to the drawings.

(Whole printer configuration)
FIG. 1 is an external perspective view of an ink jet type roll paper printer to which the present invention is applied, and FIG. 2 is an external perspective view of a state in which the opening / closing lid is fully opened. The roll paper printer 1 of this example has a printer body 2 having a substantially rectangular parallelepiped shape as a whole, and an opening / closing lid 3 attached to the front surface of the printer body 2. A recording paper discharge port 4 having a predetermined width is formed on the front surface of the outer case 2 a of the printer main body 2. A paper discharge guide 5 protrudes forward below the recording paper discharge port 4, and a lid opening / closing lever 6 is disposed on the side of the paper discharge guide 5. A rectangular opening 2b for inserting and removing roll paper is formed below the paper discharge guide 5 and the lid opening / closing lever 6 in the outer case 2a. The opening 2b is sealed by the opening / closing lid 3.

  When the lid opening / closing lever 6 is operated, the opening / closing lid 3 is unlocked. When the paper discharge guide 5 is pulled forward, as shown in FIG. 2, the opening / closing lid 3 opens until it is substantially horizontal forward with the lower end as a center. When the opening / closing lid 3 is opened, the roll paper storage unit 11 formed inside the printer is opened, and at the same time, the recording paper transport path from the roll paper storage unit 11 to the recording paper discharge port 4 is opened, and the printer is opened. The roll paper can be easily replaced from the front.

  An opening 2c is also formed on the right side of the opening / closing lid 3, and an opening / closing lid 7 that can be opened / closed around the lower end is attached thereto. When the opening / closing lid 7 is opened, the ink cartridge loading unit 18 as an ink supply unit is opened, and the ink cartridge can be replaced. The left side of the opening / closing lid 3 is an operation surface 2d, in which a status display lamp, a paper feed button, and the like are arranged.

(Internal configuration of printer)
FIG. 3 is a perspective view showing a printer mechanism portion built in the outer case 2a of the roll paper printer 1, and FIG. 4 is a schematic longitudinal sectional view when the printer mechanism portion is cut in the front-rear direction. The printer mechanism unit 10 includes a roll paper storage unit 11 at the center in the width direction, and the roll paper storage unit 11 stores the roll paper 12 in a horizontally placed state facing the printer width direction. It has become. That is, the roll paper storage unit 11 is slightly wider than the roll paper 12, and its bottom surface is defined by a curved bottom plate 11a having the deepest center in the front-rear direction of the printer. The roll paper 12 is placed in a rollable state with the front and rear outer peripheral surface portions 12b and 12c abutting against the curved bottom surface portions 11b and 11c of the bottom plate 11a.

  A head unit 13 is mounted horizontally on the upper side of the roll paper storage unit 11. The head unit 13 includes a head unit frame 14, and a carriage guide shaft 15 extends horizontally between the left and right side plate portions 14 a and 14 b of the head unit frame 14. A carriage 17 on which the inkjet head 16 is mounted in a downward state can be reciprocated along the carriage guide shaft 15.

  As shown in FIG. 3, an ink cartridge loading unit 18 and a head maintenance unit 20 are disposed in the lower part of the right side portion of the head unit 13 adjacent to the right side of the roll paper storage unit 11. An ink cartridge (not shown) can be attached to the ink cartridge loading unit 18 disposed on the lower side. The head maintenance unit 20 disposed on the upper side collects the wiper for wiping the nozzle surface of the inkjet head 16 and the waste ink discharged or discharged from each nozzle on the nozzle surface, similarly to the known head maintenance unit. A recovery unit (not shown) is provided. A lower portion of the left side portion of the head unit 13 adjacent to the left side of the roll paper storage portion 11 is a substrate mounting portion 22 on which a control substrate (not shown) is mounted.

  As shown in FIG. 4, in the printer mechanism unit 10, a recording paper guide 32 is disposed horizontally along the printer width direction at a rear portion between the roll paper storage unit 11 and the head unit 13. Yes. On the front side of the recording paper guide 32, a platen guide 33 is disposed horizontally in the front-rear direction of the printer at a position one step higher. An ink jet head 16 mounted on the carriage 17 is disposed directly above the platen guide 33. The nozzle surface 16a of the inkjet head 16 is opposed to the upper surface 33a of the platen guide 33 with a certain gap, and the printing position is defined by the upper surface 33a.

  A rear paper feed roller 34 is stretched horizontally in the printer width direction between the platen guide 33 that defines the print position and the recording paper guide 32. A rear paper pressing roller 35 having a predetermined width is pressed against the rear paper feeding roller 34 from below with a predetermined pressing force. A front-side paper feed roller 37 is disposed at a front end side portion of the platen guide 33. A front paper pressing roller 38 is pressed against the front paper feeding roller 37 from above. The rear paper feed roller 34 and the front paper feed roller 37 are driven by a paper feed motor 36 mounted on the head unit 13.

  The carriage 17 is reciprocated in the printer width direction (printing width direction) by a carriage transport mechanism including a carriage motor 39 and a timing belt 40. While the carriage 17 is reciprocated, printing is performed on the surface of the portion of the recording paper 12 a that is fed from the roll paper 12 and positioned at the printing position by the inkjet head 16 mounted thereon. After a series of line printing in the width direction of the recording paper 12a is completed, the rear paper feeding roller 34 and the front paper feeding roller 37 are rotationally driven to feed the recording paper 12a by a predetermined pitch. After this, the next line is printed. Thus, the recording paper 12a is printed by the inkjet head 16 while being intermittently sent out at a predetermined pitch.

  An ink damper 41 is mounted on the carriage 17, and a flexible ink tube 42 is connected thereto. Each color ink is supplied to the inkjet head 16 from the ink cartridge mounted on the ink cartridge loading unit 18 via the ink tube 42, and full-color printing can be performed by the inkjet head 16.

  A scissors-type recording paper cutting device 44 is disposed at the recording paper discharge port 4 from which the recording paper 12a after printing is discharged. The fixed blade 45 of the recording paper cutting device 44 is arranged vertically in the upward state, and the movable blade 46 is arranged vertically downward. When the movable blade 46 pivots in the vertical direction with one end in the printer width direction as a fulcrum by the movable blade drive mechanism 47, the contact point with the fixed blade 45 moves in the printer width direction, and the recording paper positioned between them. 12a can be cut in the width direction.

  Here, the open / close lid 3 includes a platen guide 33, a recording paper guide 32, a rear paper pressing roller 35, a front paper feeding roller 37, and a fixed blade 45 mounted on the lid frame 51. A lid opening / closing lever 6 and a paper discharge guide 5 are attached to the front end of the lid frame 51. The open / close lid 3 is configured to open and close while maintaining a horizontal state by, for example, a parallel link mechanism.

  When the opening / closing lid 3 is opened, the roll paper loading / unloading opening 2b of the roll paper storage unit 11 is opened, and the recording paper transport path from the roll paper storage unit 11 to the recording paper discharge port 4 is opened. Become. Therefore, when the roll paper 12 is stored in the roll paper storage unit 11, the recording paper 12a is pulled out from the roll paper 12 by a predetermined length, and then the opening / closing lid 3 is closed, as shown by a thick dashed line in FIG. The recording paper 12 a drawn from the roll paper 12 stored in the roll paper storage unit 11 is guided by the recording paper guide 32, and the platen guide 33 is interposed between the rear paper feeding roller 34 and the rear paper pressing roller 35. A recording paper set state is formed, which is drawn out from the recording paper discharge port 4 through the upper paper 33 and the front paper pressing roller 38 via the upper surface 33a (printing position).

  When the rear paper feed roller 34 and the front paper feed roller 37 rotate in this state, the conveyance of the recording paper 12a is started. The recording paper 12a is intermittently conveyed at a predetermined pitch, and printing is performed on the surface of the recording paper 12a that passes the printing position by the inkjet head 16. After the predetermined printing is completed, for example, the portion of the recording paper 12a after printing is discharged from the recording paper discharge port 4, and the rear end position of the printing portion of the recording paper 12a is cut by the recording paper cutting device 44, A printed piece of printed paper of length is issued.

(Roll paper feed mechanism and roll paper feed control operation)
In the roll paper printer 1 of this example, the roll paper feeding that can feed the recording paper by rotating the roll paper 12 stored in the roll paper storage unit 11 around its central axis independently of the paper feeding operation. It has a mechanism.

  FIG. 5 is an explanatory view showing a roll paper feeding mechanism. With reference to FIG. 4 and FIG. 5, the roll paper feeding mechanism of this example will be described. The roll paper feed mechanism 80 includes a feed roller 81 disposed in the roll paper storage unit 11 and a feed motor 82 for rotationally driving the feed roller 81. The feeding roller 81 is horizontally disposed on the front curved bottom surface portion 11b of the bottom plate 11a of the roll paper storage unit 11 along the printer width direction. The feeding roller 81 is a roller made of a material having a high friction coefficient such as a rubber roller. The outer peripheral surface of the feed roller 81 protrudes slightly upward from the curved bottom surface portion 11 b and is always in contact with the outer peripheral surface portion 12 b of the roll paper 12 stored in the roll paper storage portion 11.

  Both shaft ends of the roller shaft 83 of the feed roller 81 are supported by the left and right side plate portions (not shown) of the roll paper storage unit 11 in a rotatable state. A feeding motor 82 is disposed on one shaft end side of the roller shaft 83, and the rotation of the feeding motor 82 is transmitted to the roller shaft 83 via a rotational force transmission mechanism such as a reduction gear train 84. ing.

  FIG. 6 is a schematic block diagram showing a control system of the roll paper printer 1 of this example. The control system is mainly configured by a drive control unit 50 having a microcomputer. The drive control unit 50 receives a print command and print data from a host device 51 such as a host computer, and feeds paper. Perform operations and print operations. Detection signals from various sensors (not shown) such as detection signals indicating the carriage position are input to the drive control unit 50. Based on these detection signals, the drive control unit 50 controls the paper feed motor 36 and the carriage motor 39 with a motor driver. The inkjet head 16 is driven and controlled via the head driver 54. Further, the feeding motor 82 is driven and controlled via the motor driver 55.

  In the printing operation, the carriage 17 is moved in the width direction (main scanning direction) of the recording paper 12a by the carriage motor 39, and for example, the printing operation for one line is performed by the inkjet head 16 mounted thereon. Do. After the printing operation for one line is completed, the carriage 17 moved outside the printing area is stopped there, and the paper feed motor 36 is driven to feed, for example, one line of paper in the sub-scanning direction. After the paper feeding operation is completed, the carriage 17 is again moved in the reverse direction in the main scanning direction, and the printing operation for the next line is performed. The printing operation in the main scanning direction and the paper feeding operation in the sub-scanning direction are alternately repeated, and printing for a predetermined number of lines is performed on the recording paper 12a.

  The drive control unit 50 of this example is configured to perform the paper feeding operation using not only the stop period of the carriage 17 but also the deceleration period and acceleration period of the carriage 17. That is, the paper feed motor 36 feeds the paper within the carriage reversal time from the time when the carriage 17 moves out of the print area to the time when the carriage 17 starts moving in the reverse direction and enters the print area again. . As a result, the non-printing period that is not involved in printing can be shortened compared to the case where paper feeding is performed only during the stop period of the carriage 17, so that the throughput of the printing operation can be increased.

  Here, the drive control unit 50 of this example uses the period of the printing operation by the inkjet head 16 to drive the feed motor 82 and rotate the feed roller 81, thereby rotating the roll paper 12 and recording paper. 12a is extended. The feeding amount of the recording paper 12a is matched with the paper feeding amount by the paper feeding motor 36 to be performed next. As the recording paper 12a is fed out, the portion of the recording paper 12a between the roll paper 12 and the rear paper feed roller 34 becomes loose. Such slack is eliminated by the next paper feeding operation. Therefore, since the inertia load of the roll paper 12 does not act as the paper feed load on the rear paper feed roller 34, the paper feed load of the roller 34 is greatly reduced.

  FIG. 7 is an operation explanatory diagram illustrating a printing operation, a paper feeding operation, and a roll paper feeding operation realized by the drive control unit 50. In the drawing, the upper curve A is a curve indicating the movement state of the carriage 17, the central curve B is a curve indicating the paper feed state, and the lower curve C is a change in the feeding amount (slack amount) of the recording paper 12a. It is a curve which shows. Curves A and B have time on the horizontal axis and speed on the vertical axis. Curve C is obtained by taking time on the horizontal axis and feeding amount Δ (sagging amount) on the vertical axis.

  Referring to FIG. 7, the carriage 17 that has finished printing in the main scanning direction decelerates from a point just before the time when it deviates laterally from the print area of the recording paper 12a (printing end time T1) and stops at time T3. . The stop period of the carriage 17 is from the time point T3 to the time point T4. From the time point T4, the carriage 17 starts to move in the reverse direction of the main scanning direction and is accelerated to a predetermined speed. When the carriage 17 again enters the printing area of the recording paper 12a (time T6), the printing operation on the recording paper 12a by the inkjet head 16 is started.

  The feeding operation period of the recording paper 12a by the paper feeding motor 36 is, for example, a fixed time from time T2 to time T5. The paper feed motor 36 is a stepping motor, for example, and is driven and controlled at a predetermined step rate.

  On the other hand, the rotation of the roll paper feed roller 81 by the feed motor 82 starts at the paper feed end time T5 and ends at the next paper feed start time T2. That is, it is continuously performed in the period from the paper feed end time T5 to the print start time T6, the print period, and the period from the print end time T1 to the paper feed start time T2. The roll paper 12 is rotated in the recording paper feeding direction by the rotation of the feeding roller 81, and the recording paper 12a is fed out. As shown by the curve C, the feeding amount (slack amount) of the recording paper 12a reaches the maximum Δ (max) at the paper feeding start time T2 by the paper feeding motor 36. This feed amount is the same as the paper feed amount between time T2 and time T5. Accordingly, the feeding amount of the recording paper 12a becomes zero at the paper feeding end time T5. That is, the amount of slack in the portion of the recording paper 12a between the roll paper 12 and the rear paper feed roller 34 becomes zero.

  As described above, in the roll paper printer 1 of this example, the roll paper 12 is stored in a state where it is on the feed roller 81 disposed on the bottom plate 11 a of the roll paper storage unit 11. The feeding roller 81 is driven only during a period during which no paper is fed (a period from time T5 to time T2 in FIG. 7), and the roll paper 12 on the feeding roller 81 rotates around its central axis. From there, the recording paper 12a is fed out. At the time of starting the paper feed, a slack corresponding to the paper feed amount by the rear paper feed roller 34 driven by the paper feed motor 36 occurs.

  Therefore, during paper feeding, the inertial load of the roll paper 12 does not directly act on the rear paper feeding roller 34, and the paper feeding load of the rear paper feeding roller 34 is greatly reduced. For this reason, even when the paper feeding speed is increased and the intermittent paper feeding interval is reduced, it is not necessary to increase the paper feeding force of the rear paper feeding roller in order to prevent slipping. Accordingly, since it is not necessary to increase the pressing force by the rear paper pressing roller 35, it is not necessary to increase the torque of the paper feeding motor 36, and the durability of the rear paper pressing roller 34 and the rear paper pressing roller 35 is improved. Decreasing can also be avoided.

  Furthermore, it is possible to avoid the roll paper 12 from being lifted from the bottom plate 11a of the roll paper storage unit 11 without being able to rotate following the recording paper feed operation therefrom during paper feeding. That is, since the recording paper 12a between the rear paper feeding roller 34 and the roll paper 12 is slack, even if the recording paper 12a is pulled in the feeding direction by the rear paper feeding roller 34, the tensile force is applied to the roll paper. 12 does not act. Therefore, the roll paper 12 does not float at the start of paper feeding. For this reason, it is possible to avoid an adverse effect that an excessive load is applied to the rear paper feed roller 34 when the roll paper 12 that has been lifted falls and the recording paper 12a slips, and the paper can be fed with high accuracy.

  Furthermore, in this example, the feed amount (slack amount) of the recording paper 12a is set to be the same as the paper feed amount at the next paper feed. Therefore, at the end of the paper feeding operation (time T5 in FIG. 7), the state returns to the state without slack. If the recording paper feed amount (slack amount) is larger than the paper feed amount, the recording paper slack gradually increases and a danger such as paper jam occurs on the front side of the rear paper feed roller 34. There is sex. Conversely, when the recording paper feed amount is smaller than the paper feed amount, the inertia load of the roll paper is applied to the rear paper feed roller 34 in the latter half of the paper feed operation, the paper feed load increases, and slipping occurs. As a result, the paper feeding accuracy may be reduced. In this example, occurrence of such harmful effects can be prevented.

(Other embodiments)
In the above example, the period during which the paper feeding operation is performed is removed, and the feeding roller 81 is rotationally driven to perform the feeding operation of the recording paper 12a. In parallel with the paper feeding operation, the feeding operation of the recording paper 12 a may be performed while the roll paper 12 is rotated by the feeding roller 81. By utilizing both the paper feeding operation period and the printing operation period, the recording paper 12a can be fed while the feeding roller 81 is rotated at an extremely low speed. Therefore, the feeding motor 82 is small and has a small torque capacity. A motor can be used. Of course, the recording paper 12a can be fed out during a part of the period other than the period during which the paper feeding operation is performed, and within the period of the paper feeding operation (time points T2 to T5 in FIG. 7). It can also be done.

  In the above example, the present invention is applied to a serial type roll paper printer. However, the present invention is also applicable to a line type roll paper printer. In the above example, the present invention is applied to an ink jet type roll paper printer. However, the present invention is also applicable to a roll paper printer including various print heads such as a thermal head. .

  DESCRIPTION OF SYMBOLS 1 Roll paper printer, 2 Printer main body, 3 Opening / closing lid, 4 Recording paper discharge port, 11 Roll paper storage part, 11a Bottom plate, 11b, 11c Curved bottom surface part, 12 Roll paper, 12a Recording paper, 12b, 12c Outer surface part, 13 Head unit, 33 Platen guide, 34 Rear paper feed roller, 34a Roller shaft, 35 Rear paper press roller, 36 Paper feed motor, 37 Front paper feed roller, 38 Front paper press roller, 44 Recording paper cutting device, 50 Drive control unit, 52, 53, 55 motor driver, 54 head driver, 80 roll paper feed mechanism, 81 feed roller, 82 feed motor, 83 reduction gear train.

Claims (6)

A roll paper storage section for storing the roll paper in a rollable state;
A feeding roller disposed at a position capable of contacting the outer peripheral surface of the roll paper stored in the roll paper storage unit;
A print head;
A paper feed roller for conveying the long recording paper fed from the roll paper in the roll paper storage unit via the print position by the print head;
A paper feed motor for rotationally driving the paper feed roller;
A roll paper printer comprising a feeding motor for rotationally driving the feeding roller. The roll paper printer according to claim 1.
A controller that rotates the feed roller using one or both of the period of the printing operation by the print head and the period of the paper feeding operation by the paper feeding roller performed following the printing operation; A roll paper printer comprising: The roll paper printer according to claim 2.
The roll paper printer, wherein the control unit rotates the feed roller so that the roll paper rotates in the recording paper feed direction by an amount corresponding to a paper feed amount necessary for the paper feed operation. A roll paper feeding control method for a roll paper printer according to claim 1,
The feeding roller is rotated using one or both of the period of the printing operation by the print head and the period of the paper feeding operation by the paper feeding roller performed following the printing operation. A roll paper feed control method for a roll paper printer. In the roll paper feeding control method of the roll paper printer according to claim 4,
A roll paper feed control method for a roll paper printer, characterized in that the feed roller is rotated so that the roll paper is rotated in the recording paper feed direction by an amount corresponding to a paper feed amount required for the paper feed operation. A roll paper feeding mechanism for feeding out long recording paper from roll paper stored in a rollable state in a roll paper storage section of a roll paper printer,
A feeding roller disposed at a position capable of contacting the outer peripheral surface of the roll paper stored in the roll paper storage unit;
Independent of a paper feed roller for transporting a long recording paper fed from the roll paper in the roll paper storage section via a printing position, a feed motor for rotating the feed roller is provided. A roll paper feed mechanism characterized by

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