JP2010202305A - Mechanism for guiding recording paper and paper roll printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mechanism for guiding recording paper guiding the recording paper appropriately. <P>SOLUTION: In the tension guide 27 of the mechanism 26 for guiding the recording paper giving tension to the recording paper 12a pulled out of the paper roll 12 of a paper roll storing section 11 of a paper roll printer 1, only a protruded guide surface section 42a slightly protruded to the recording paper guide surface 28 is brought into a condition substantially biasing the recording paper 12a. The protruded guide surface section 42a has width narrower than the width size of a conveyance passage, and is formed bilaterally symmetrically relative to its center, therefore, a condition biasing the central part of the conveyed recording paper 12a in the width direction is formed. A biasing force is applied only to the central part in the width direction in the recording paper when the width of the protruded guide surface section is formed to be narrow adequately. That can prevent the biasing force applied to the recording paper 12a from becoming unbalanced due to influence of inclination of the recording paper guide surface 28 or a shape error, and moreover, suppress meandering or skew of the recording paper. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a recording paper guide mechanism used for a roll paper printer or the like that performs printing on a long recording paper fed out from a roll paper stored in a roll paper storage unit, and in particular while acting on the tension of the recording paper. The present invention relates to a recording paper guide mechanism for guiding the recording paper along a conveyance path.

In roll paper printers that issue receipts and 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, and the recording paper is drawn from the roll paper stored in the roll paper storage unit. Printing is performed by conveying the paper toward the printing position via a paper feed roller.
If the feed load acting on the paper feed roller fluctuates from the recording paper drawn from the roll paper,
A slip occurs between the recording paper and the paper feeding roller, and the paper feeding accuracy of the recording paper passing through the printing position is lowered, which may lead to deterioration of printing quality. In particular, in the case of a roll paper storage unit called a throwing method in which the roll paper is not supported by a support shaft such as an unwinding reel and is simply placed in a rollable state on the bottom surface of the roll paper storage unit. Feed load fluctuation is large.

Therefore, in order to suppress fluctuations in the recording paper feed load, a tension guide that holds the recording paper in a state of being biased by a spring force is attached in the middle of the conveyance path drawn from the roll paper to the printing position. When the tension acting on the recording paper from the roll paper side fluctuates, the tension guide biased by the spring force moves accordingly, and the tension fluctuation acting on the paper feed roller side is alleviated. It is possible to prevent the paper feeding accuracy from being lowered by the roller. Patent Document 1 discloses a printer including such a tension member.

JP2007-99458

Here, since the tension guide is supported so as to be movable in accordance with a change in the recording paper feed load, an inclination may occur in the width direction due to an attachment error or the like. Further, the guide surface of the tension guide is a convex bent surface for urging the recording paper, and the guide surface may cause a shape error in the width direction. If the tension guide is tilted and there is variation in shape, the frictional force generated between the guide surface of the tension guide and the recording paper may vary on both sides in the width direction, which may cause the recording paper to meander and skew. is there.

In particular, in the roll paper printer, the width of the recording paper is regulated only by the left and right guide plates that define the storage width of the roll paper storage section, and from here on the transport path via the printing position. In many cases, a guide for regulating the position in the width direction is not arranged. Therefore, if the left and right paper feed loads vary in the middle of the transport path, the recording paper is likely to meander and skew, and a paper jam may occur.

In view of this point, an object of the present invention is to provide a recording paper guide mechanism capable of guiding a recording paper while applying tension without causing meandering and skewing, and roll paper provided with the recording paper guide mechanism. To propose a printer.

In order to solve the above problems, the present invention is a recording paper guide mechanism for guiding a recording paper along a conveyance path,
A tension guide having a recording paper guide surface defining a part of the transport path;
A biasing member that biases the tension guide in a direction in which the recording paper guide surface is pressed against the recording paper transported along the transport path;
A protruding guide surface portion protruding from the recording paper guide surface,
The protruding guide surface portion has a width narrower than the width dimension of the transport path.

In the recording paper guide mechanism of the present invention, since the protruding guide surface portion is formed on the recording paper guide surface that urges the recording paper, substantially only the protruding guide surface portion is pressed against the recording paper. The protruding guide surface portion has a width that is narrower than the width dimension of the transport path, and a state in which a part of the transported recording paper in the width direction is biased is formed. Therefore, if the width of the protruding guide surface portion is sufficiently narrow, it is possible to prevent or suppress the urging force acting on the recording paper from falling into an unbalanced state in the width direction. As a result, meandering and skewing of the recording paper can be prevented or suppressed.

Here, it is preferable that the width dimension of the protruding guide surface portion is a narrow width that is 1/3 or less of the width dimension of the transport path. Further, it is preferable that the protruding guide surface portion is formed substantially symmetrically with respect to the center in the width direction of the transport path.

Since it is formed symmetrically with respect to the center, a state in which the central portion in the width direction of the recording paper to be conveyed is urged with a narrow width is formed. Therefore, the urging force acts only on the central portion in the width direction of the recording paper. Therefore, when the recording paper guide surface is inclined in the width direction, the biasing force acting on the recording paper falls into an unbalanced state on the left and right in the width direction when the recording paper guide surface has a variation in shape in the width direction. This can be prevented or suppressed.

Further, the protruding guide surface portion may be a plurality of divided protruding guide surface portions formed in a separated state in the width direction of the transport path, instead of being a continuous surface in the width direction. In this case, the sum of the width dimensions of the divided protruding guide surface portions may be made smaller than the width dimension of the transport path, and it is desirable to make it not more than 1/3 of the width dimension of the transport path.

Further, if the width of the protruding guide surface portion biased by the recording paper is reduced, the pressure contact force per unit area between them increases, so that the protruding guide surface portion is connected to the other portion of the recording paper guide surface. Compared to the above, it is desirable to use a low friction surface having a small frictional resistance with the recording paper.

In this case, the protruding guide surface portion can be defined by the surface of a low friction sheet having a predetermined thickness laminated on the recording paper guide surface.

Further, the recording paper guide surface for urging the recording paper may include a convex curved surface that is curved along the recording paper conveyance direction.

Further, the protruding guide surface portion can be formed at least on the convex curved surface of the recording paper guide surface. The convex curved surface of the recording paper guide surface where the tension of the recording paper is applied most, and by contacting the recording paper with a narrow width, the urging force acting on the recording paper is more effectively unbalanced in the right and left in the width direction. Can be prevented or suppressed.

Next, the roll paper printer of the present invention is
A roll paper storage section;
A print head for printing on a long recording paper fed out from the roll paper stored in the roll paper storage unit;
A platen defining the print position of the print head;
A recording paper guide mechanism for guiding the recording paper toward the platen;
The recording paper guide mechanism configured as described above is employed as the recording paper guide mechanism.

In this case, in the case where the roll paper storage unit is a throw-type roll paper storage unit in which the recording paper is simply stored in a rollable state without being rotatably supported around the support shaft,
A conveyance path portion between the recording paper guide mechanism and the platen is defined by a paper feed roller and a first paper press roller that is rotated by the paper feed roller, and the recording paper guide mechanism and the roll It is desirable that the conveyance path portion between the paper storage units is defined by a feeding roller and a second paper pressing roller that is pressed against the feeding roller and rotates. In this way, by controlling the rotation of the feeding roller and the paper feeding roller, the recording paper can be transported toward the printing position under an appropriate paper feeding load without causing slack in the recording paper. .

In the recording paper guide mechanism of the present invention, a narrow protruding guide surface portion is formed at the central portion in the width direction of the recording paper guide surface of the recording paper guide for biasing the recording paper, and recording is performed by the protruding guide surface portion. The paper can be energized. Since only the central part in the width direction of the recording paper is urged, if the recording paper guide surface is tilted in the width direction and the surface shape varies in the width direction, the recording paper width direction generated by the urging force It is possible to prevent or suppress the paper feed load from becoming unbalanced in the width direction. Therefore, the recording paper can be conveyed linearly along the conveyance path without meandering and skewing.

In particular, the recording paper guide mechanism of the present invention is suitable for use in a roll paper printer that does not have a guide for regulating the width direction of the recording paper in the conveyance path from the roll paper storage unit to the printing position. Yes.

1 is a perspective view of a roll paper printer to which the present invention is applied. It is a perspective view of a roll paper printer in a state where the open / close lid is fully opened. It is a schematic longitudinal cross-sectional view for showing the internal structure of a roll paper printer. It is a schematic longitudinal cross-sectional view of the roll paper printer in a state where the open / close lid is fully opened. It is explanatory drawing which shows the paper feed system of a roll paper printer. It is a perspective view showing a tension guide of the recording paper guide mechanism.

Embodiments of a roll paper printer provided with a recording paper guide mechanism of the present invention will be described below with reference to the drawings.

(overall structure)
FIG. 1 is an external perspective view of an ink jet roll paper printer to which the present invention is applied.
FIG. 2 is an external perspective view of the state where the opening / closing lid is fully opened. The roll paper printer 1 has a printer body 2 having a substantially rectangular parallelepiped shape as a whole, and an open / close 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 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. After unlocking, when the paper discharge guide 5 is pulled forward, the opening / closing lid 3 is moved substantially forward with its lower end as a center by a link mechanism to which the opening / closing lid 3 is attached, for example, a four-link parallel link mechanism 3A. Open until level. When the opening / closing lid 3 is opened, as shown in FIG. 2, the roll paper storage unit 11 formed inside the printer is opened, and at the same time, the recording paper is conveyed from the roll paper storage unit 11 to the recording paper discharge port 4. The path is opened, and roll paper replacement work can be easily performed from the front of the printer.

(Internal structure)
FIG. 3 is a schematic longitudinal sectional view showing the internal structure of the roll paper printer 1, and FIG. 4 is a schematic longitudinal sectional view when the open / close lid 3 is fully opened. Inside the roll paper printer 1, a roll paper storage unit 11 is formed at the center in the width direction of the printer main body frame 10.
The roll paper storage unit 11 includes a tray 13 in which the roll paper 12 is stored so as to be able to roll in a horizontal state facing the printer width direction, and a guide roller 14 extending in the printer width direction is attached to a front portion thereof. It has been.

In the upper position on the rear side of the roll paper storage unit 11, a feeding roller 15 that is horizontally stretched in the width direction of the printer by the printer main body frame 10 is disposed. The feeding roller 15 has a paper pressing roller 16 from the front side. Is pressed. The feeding roller 15 is rotationally driven by a feeding motor 17 attached to the printer main body frame 10. The paper presser roller 16 is supported by a support lever 18, and the support lever 18 is attached to the opening / closing lid 3. When the opening / closing lid 3 is opened, the paper presser roller 16 is separated from the paper feed roller 16. Yes.

A head unit frame 20 is horizontally attached to the upper end of the printer main body frame 10 above the roll paper storage unit 11. A carriage guide shaft 21 is stretched horizontally across the head unit frame 20 in the printer width direction. A carriage 23 on which the ink-jet head 22 is mounted in a downward state is capable of reciprocating along the carriage guide shaft 21 in the printer width direction. The carriage 23 is reciprocated in the printer width direction by a known carriage conveyance mechanism, for example, a carriage conveyance mechanism including a carriage motor and a timing belt.

A platen frame 24 that extends horizontally in the front-rear direction of the printer is disposed below the inkjet head 22. A platen 25 facing the inkjet head 22 with a certain gap is attached to the platen frame 24 horizontally in the printer width direction, and the printing position of the inkjet head 22 is defined by the platen 25.

A recording paper guide mechanism 26 is attached to the rear end of the platen frame 24. The recording paper guide mechanism 26 includes a tension guide 27 on which a long recording paper 12 a drawn out from the roll paper 12 stored in the roll paper storage unit 11 is bridged. The tension guide 27 includes a recording paper guide surface 28 having a convex curved surface shape along the recording paper conveyance direction.
The tension guide 27 is centered on a support shaft 29 that extends horizontally in the printer width direction at the rear end of the platen frame 24 so that the recording paper guide surface 28 can move in a direction toward and away from the recording paper 12a. It is mounted so that it can pivot up and down. Spindle 29
An urging member 30 such as a torsion spring is attached to the urging member 30.
The recording paper guide surface 28 of the tension guide 27 is urged against the recording paper 12a.

Next, a paper feed roller 31 is stretched horizontally in the printer width direction at a position in front of the tension guide 27 in the platen frame 24. A paper pressing roller 32 attached to the head unit frame 20 side is pressed against the paper feeding roller 31 from above with a predetermined pressing force via the recording paper 12a. A front paper feed roller 33 is stretched horizontally in the width direction of the printer at a portion of the platen frame 24 on the front end side of the platen 25. A front paper pressing roller 34 attached to the head unit frame 20 side is pressed against the front paper feeding roller 33 from above through the recording paper 12a.

The paper feed roller 31 and the front paper feed roller 33 are driven by a paper feed motor 35 attached to the printer main body frame 10 on the rear side of the roll paper storage unit 11. In this example, a reduction gear train (not shown) is mounted on the platen frame 24, and the rotational force of the paper feed motor 35 is transmitted to the paper feed roller 31 and the front paper feed roller 33 through the reduction gear train. These rollers 31 and 33 rotate synchronously.

In the vicinity of the recording paper discharge port 4, an auto cutter 36 for cutting the leading end portion of the recording paper 12a after printing in the width direction is disposed. The recording paper 12a is cut into a predetermined length by the auto cutter 36 and issued as a receipt, a ticket, or the like.

Here, on the side of the opening / closing lid 3, one blade of the platen 25, the paper feed roller 31, the downstream paper feed roller 33, the paper press roller 16, the recording paper guide mechanism 26, and the auto cutter 36 is mounted. . When the opening / closing lid 3 is opened, as shown in FIG. 4, the recording paper path A (path indicated by a one-dot chain line in FIG. 3) from the roll paper storage unit 11 to the recording paper discharge port 4 is opened, and the roll paper is replaced. Work and recording paper setting work can be performed easily.

(Paper feed operation)
In the roll paper printer 1 configured as described above, the recording paper 12a drawn upward from the roll paper 12 stored in the roll paper storage unit 11 is a feeding roller 15 and a paper pressing roller as shown by a thick chain line in FIG. 16 through the recording paper guide mechanism 2
The paper feed roller 3 is stretched over the tension guide 27 and bent forward.
1 and the paper pressing roller 32, between the inkjet head 22 and the platen 25, and between the front paper feeding roller 33 and the front paper pressing roller 34, and is pulled out from the recording paper discharge port 4. Set. In this state, the tension guide 27 is pushed downward by the recording paper 12a, and the recording paper 12a is given a predetermined tension by the urging force of the urging member 30.

FIG. 5 is an explanatory diagram showing a paper feed system of the roll paper printer 1. The drive control unit 41 of the roll paper printer 1 controls the drive of each unit based on a command from a host device such as a computer system (not shown). In the printing operation, the paper feed motor 35 is driven to rotate the paper feed roller 31 and the front paper feed roller 33, and in synchronization with this, the feeding motor 17 is rotationally driven to carry the recording paper 12a. I do. Further, the recording paper 12a passing through the printing position by driving the inkjet head 22 in synchronization with the conveyance of the recording paper 12a.
Print on the surface. After a series of line printing in the width direction of the recording paper 12a is completed, the feeding roller 15, the paper feeding roller-31 and the front paper feeding roller 33 are rotationally driven to feed the recording paper 12a by a predetermined pitch. Is printed. In this manner, the recording paper 12a is printed by the inkjet head 22 while being intermittently sent out at a predetermined pitch.

When the feeding operation of the recording paper 12a is performed intermittently, the feeding load of the recording paper 12a varies due to the inertial force of the roll paper 12 and the like. The fluctuation of the feed load is suppressed or alleviated when the tension guide 27 urged by the urging member 30 pivots up and down. Therefore, the adverse effect that the paper feeding accuracy is lowered due to the fluctuation of the feeding load and the printing quality is lowered is solved.

The drive control unit 41 monitors a detection signal from the guide sensor 37 of the recording paper guide mechanism 26 in the printing operation. The guide sensor 37 is a tension guide 27.
This is for detecting the swiveling position. For example, the sensor output is turned off when the recording paper 12a is in an appropriate tension state, the recording paper 12a is in a slack state, and the sensor output is turned on when the tension guide 27 is swung largely by the biasing force. . Based on the output of such a guide sensor 37, the recording paper 12a is synchronized with the driving of the paper feed roller 31 and the front paper feed roller 33 so that the recording paper 12a is conveyed in a constant tension state without causing slack. The driving of the feeding roller 15 on the paper storage unit side is controlled.

After the end of printing, the auto cutter 36 disposed near the recording paper discharge port 4 is driven to cut the recording paper 12a. As a result, a receipt, a ticket, and the like having a predetermined length obtained by cutting the recording paper 12a are issued from the recording paper discharge port 4.

(Tension guide for recording paper guide mechanism)
FIG. 6A is a perspective view showing the tension guide 27 of the recording paper guide mechanism 26 taken out. The tension guide 27 of this example is, for example, a plastic molded product, and includes an arcuate guide plate portion 27a and side plate portions 27b and 27c formed on both sides thereof.
The shaft holes 27d and 27e of the support shaft 29 are formed in 7b and 27c. The outer surface of the arcuate guide plate portion 27a is a recording paper guide surface 28 that is urged against the recording paper 12a.

The recording paper guide surface 28 has a width W1 corresponding to the width of the recording paper conveyance path A (see FIGS. 3 and 5). A low friction sheet 42 having a constant width W2 and a constant thickness is attached to the central portion of the recording paper guide surface 28 in the width direction so as to be symmetric with respect to the center in the width direction. The sheet surface is a protruding guide surface portion 42 a that slightly protrudes from the other recording paper guide surface 28. The low friction sheet 42 is formed of a material having a smaller coefficient of friction with the recording paper 12 a than the recording paper guide surface 28.

For example, when the paper width of the conveyed recording paper 12a is 30 mm to 114 mm, the recording paper guide surface 28 is set to a width W1 larger than this width. On the other hand, the width W2 of the protruding guide surface portion 42a is set to a narrow width of 1/3 or less of the width W1. Further, the low friction sheet 42
Is set to about 0.6 mm to 0.8 mm, and the protruding guide surface portion 42 a is a surface protruding from the recording paper guide surface 28 by the same amount.

Thus, the tension guide 27 has a recording paper guide surface 28 for urging the recording paper 12a.
In addition, a projecting guide surface portion 42a having a narrower height is formed. Accordingly, substantially only the protruding guide surface portion 42a is pressed against the recording paper 12a. The protruding guide surface portion 42a has a width that is sufficiently narrower than the width dimension of the transport path, and is formed symmetrically with respect to the center thereof, so that the central portion in the width direction of the recording paper 12a being transported is urged. A state is formed.

Therefore, the urging force acts only on the central portion in the width direction of the recording paper 12a by the protruding guide surface portion 42a. Therefore, when the recording paper guide surface 28 is inclined in the width direction, and the recording paper guide surface 28 has a variation in shape in the width direction, the recording paper 1
It is possible to prevent or suppress the urging force acting on 2a from falling into an unbalanced state on the left and right in the width direction. As a result, meandering and skewing of the recording paper 12a drawn out by the paper feed roller 31 can be prevented or suppressed.

In addition, without using another member such as the low friction sheet 42, the protruding guide surface portion 42a,
The recording paper guide surface 28 may be formed integrally with the central portion. Further, the protruding guide surface portion 42a may be composed of a plurality of narrow divided divided guide surface portions 43 separated in the width direction, as shown in FIG. 6B, instead of a continuous surface. Good. Also in this case, the divided protruding guide surface portions 43 are arranged symmetrically with respect to the center in the width direction, and the total width (2 × W3) of these divided protruding guide surface portions is equal to the width W1 of the recording paper conveyance path. What is necessary is just to make it become 1/3 or less. For example, as shown in FIG. 6C, such a divided protruding guide surface portion is formed by forming a plurality of vertical ribs 44 having a predetermined height at a predetermined interval in the width direction on the recording paper guide surface 28.
It can also be defined by the upper end surfaces 44 a of the vertical ribs 44.

In the above example, the arc guide plate is used as the tension guide. However, it is of course possible to use other shapes, for example, a roll-shaped tension roll can be used.

1 Roll paper printer 2 Printer body 2a Exterior case 3 Open / close lid 3A
Parallel link mechanism, 4 recording paper discharge port, 5 paper discharge guide, 6 lid opening / closing lever, 10 printer body frame, 11 roll paper storage, 12 roll paper, 12a recording paper, 13 tray, 14 guide roller, 15 feed roller, 16 Paper press roller, 17
Feed motor, 18 support lever, 20 head unit frame, 21 carriage guide shaft, 22 inkjet head, 23 carriage, 24 platen frame,
25 Platen, 26 Recording paper guide mechanism, 27 Tension guide, 27a Arc-shaped guide plate portion, 27b, 27c Side plate portion, 27d, 27e Shaft hole, 28 Recording paper guide surface, 29 Support shaft, 30 Biasing member, 31 Paper feed Roller, 32 Paper press roller, 33
Front paper feed roller, 34 Front paper press roller, 35 Paper feed motor, 36 Auto cutter, 37 Guide sensor, 41 Drive control unit, 42 Low friction sheet, 42a Projection guide surface part, 43 Divided projection guide surface part, A Recording paper Transport route

Claims (8)

A recording paper guide mechanism for guiding recording paper along a conveyance path,
A tension guide having a recording paper guide surface defining a part of the transport path;
A biasing member that biases the tension guide in a direction in which the recording paper guide surface is pressed against the recording paper transported along the transport path;
A protruding guide surface portion protruding from the recording paper guide surface,
The projecting guide surface portion has a width narrower than a width dimension of the transport path. The projecting guide surface portion has a width dimension that is approximately １ ／ or less of the width dimension of the transport path, and the projecting guide surface section is formed substantially symmetrically with respect to the center in the width direction of the transport path. The recording paper guide mechanism according to claim 1. The protruding guide surface portion is composed of a plurality of divided protruding guide surface portions formed in a state separated in the width direction of the transport path,
The recording paper guide mechanism according to claim 1, wherein the width dimension of the protruding guide surface portion is a sum of width dimensions of the divided protruding guide surface portions. 4. The protruding guide surface portion is a low friction surface having a small frictional resistance with the recording paper as compared with other portions of the recording paper guide surface. The recording paper guide mechanism according to the section. 5. The recording paper guide mechanism according to claim 1, wherein the recording paper guide surface includes a convex curved surface that is curved along a recording paper conveyance direction. 6. 6. The recording paper guide mechanism according to claim 5, wherein the protruding guide surface portion is formed at least on the convex curved surface of the recording paper guide surface. A roll paper storage section;
A print head for printing on a long recording paper fed out from the roll paper stored in the roll paper storage unit;
A platen defining the print position of the print head;
A recording paper guide mechanism for guiding the recording paper toward the platen;
A roll paper printer, wherein the recording paper guide mechanism is the recording paper guide mechanism according to any one of claims 1 to 6. A conveyance path portion between the recording paper guide mechanism and the platen is defined by a paper feed roller and a first paper press roller that is rotated by the paper feed roller.
A roll characterized in that a conveyance path portion between the recording paper guide mechanism and the roll paper storage unit is defined by a feeding roller and a second paper pressing roller that is pressed by the feeding roller and rotates. Paper printer.

Images