ROLL PAPER PRINTER

A roll paper printer includes a case that includes an accommodation section configured to accommodate roll paper, a cover that rotates about a cover hinge located below the case, and opens and closes the accommodation section, in which the cover includes a cover guide configured to guide the roll paper, the cover guide includes a first cover guide, a second cover guide, and a third cover guide disposed toward the cover hinge, the first cover guide and the second cover guide are configured to come into contact with the roll paper having a first diameter, whereas the third cover guide does not come into contact with the roll paper having the first diameter, when the cover is closed, and the third cover guide is inclined downward toward the accommodation section, and is configured to guide the roll paper to the accommodation section, when the cover is opened.

The present application is based on, and claims priority from JP Application Serial Number 2022-173072, filed Oct. 28, 2022, the disclosure of which is hereby incorporated by reference herein in its entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to a roll paper printer.

2. Related Art

In the related art, as described in JP-A-2008-120069, a printer provided with a mechanism that corrects curl of roll paper is known.

In the printer described above, it may be difficult for a user to accommodate the roll paper due to a configuration of the mechanism that corrects the curl of the roll paper or the like.

SUMMARY

The present disclosure is a roll paper printer including a case that is configured to include an accommodation section configured to accommodate roll paper wound with paper, a cover that is configured to rotate about a cover hinge located below the case, and is configured to open and close the accommodation section, a paper guide that is configured to guide the paper, and a protrusion that is configured to come into contact with the paper, and is configured to move toward the paper guide, in which the cover includes a cover guide configured to guide the roll paper, the cover guide includes a first cover guide, a second cover guide, and a third cover guide disposed in this order toward the cover hinge, the first cover guide and the second cover guide are configured to come into contact with the roll paper having a first diameter, whereas the third cover guide does not come into contact with the roll paper having the first diameter, when the cover is closed, and the third cover guide is inclined downward toward the accommodation section, and is configured to guide the roll paper to the accommodation section, when the cover is opened.

DESCRIPTION OF EMBODIMENTS

1. Configuration of Roll Paper Printer

Hereinafter, a roll paper printer1according to an embodiment will be described with reference toFIGS.1to10. It should be noted that the directions in the drawings will be described by using a three-dimensional coordinate system. For convenience of description, a positive direction of a Z axis is referred to as an up direction, upward, or simply up, a negative direction of the Z axis is referred to as a down direction, downward, or simply down, a positive direction of an X axis is referred to as a right direction, rightward, or simply right, a negative direction of the X axis is referred to as a left direction, leftward, or simply left, a positive direction of a Y axis is referred to as a front direction, forward, or simply front, and a negative direction of the Y axis is referred to as a rear direction, rearward, or simply rear.

The roll paper printer1according to the embodiment is used, for example, in a point-of-sale (POS) system. The POS system is a system used in the retail business, such as shopping centers, department stores, convenience stores, and in-car sales, and the food and beverage business, such as restaurants, coffee shops, and taverns. The roll paper printer1used in the POS system prints receipts, coupons, tickets, and the like according to products or services.

FIG.1illustrates a perspective view of the roll paper printer1when roll paper R is not accommodated in an accommodation section12in a state in which a cover10is opened forward. The roll paper printer1is installed on a table or the like on a horizontal surface with a bottom surface facing down. Here, a posture in which the roll paper printer1can open the cover10forward in one direction of a side surface of a case11, that is, a so-called vertical installation posture is illustrated. Since there is no roll paper R, a sensor6that detects a remaining amount of the roll paper R is at a position A0advanced upward in the accommodation section12.

It should be noted that a width of the accommodation section12in the left-right direction is a width W, and the roll paper R up to the width W can be accommodated. The width W is, for example, 80 mm.

The cover10can open and close the accommodation section12. A user can access the accommodation section12by opening the cover10toward the front.

FIG.2illustrates a sectional view of the roll paper printer1when the roll paper R is not accommodated in the accommodation section12in a state in which the cover10is closed. It should be noted thatFIGS.2to6and8illustrate sectional views of the roll paper printer1in a state in which the cover10is closed, andFIGS.9to10illustrate sectional views of the roll paper printer1in a state in which the cover10is opened.

The roll paper printer1includes a head2, a platen3which is a transport roller, a paper guide4, a protrusion5, and a cutter14, in addition to the sensor6and the accommodation section12. In addition, the roll paper printer1is provided with a controller (not illustrated) including a processor that can control each section.

The head2, the protrusion5, the sensor6, the accommodation section12, and a stationary blade14bof the cutter14are mounted on the case11. On the other hand, the platen3, the paper guide4, a roller7which is a contact member, a cover guide9, and a movable blade14aof the cutter14are mounted on the cover10.

The cover10is attached to the side surface of the case11by a cover hinge10a. The cover10can rotate about the cover hinge10a. The cover hinge10ais at a position opposite to the head2located above the case11. That is, the cover hinge10ais located below the case11and near the bottom surface.

When the cover10is closed, a discharge port13having a rectangular shape is formed at a boundary between the cover10and the case11.

In addition, when the cover10is closed, the platen3mounted on the cover10is at a position that faces the head2mounted on the case11.

Further, in this case, the movable blade14aof the cutter14mounted on the cover10is at a position that faces the stationary blade14bmounted on the case11.

The sensor6is mounted on the accommodation section12and is configured to detect the remaining amount of the roll paper R. The sensor6has a lever shape, and can rotate about a sensor hinge6a. In the present embodiment, since an angle at which the sensor6rotates is small, it can be approximately regarded that the sensor6can move in the up-down direction. Hereinafter, the sensor6will be described as moving to the up direction or the down direction. In addition, the sensor6is configured to advance and retreat with respect to a third accommodation section12c, which will be described below.

An elastic member (not illustrated), such as a spring, is attached on the periphery of the sensor hinge6a, and presses the sensor6to rotate clockwise. The sensor6is pressed upward by the elastic member.

The sensor6includes a detector (not illustrated) that can detect a position of the sensor6. It should be noted that the detector may be a mechanical type, such as a switch, or may be an optical type, such as a photo sensor. The sensor6is also referred to as a near end sensor.

As illustrated inFIG.8, which will be described below, as a diameter of the roll paper R is reduced, the sensor6is at the highest position A0due to a pressing force of the elastic member. In addition, even when the roll paper R is not accommodated in the accommodation section12, the sensor6is at the position A0.

When the sensor6is at the position A0, the sensor6can detect a so-called near end, which is a state in which a remaining amount of paper P wound on the roll paper R is reduced. As described above, the sensor6can detect the remaining amount of the roll paper R. The controller can know whether or not the roll paper R is at the near end as the remaining amount of the roll paper R by the sensor6.

On the other hand, the sensor6does not detect the near end when the sensor6is at a position other than the position A0. That is, when the sensor6is at the position other than the position A0, the sensor6can detect that the remaining amount of the roll paper R is sufficient.

The roll paper printer1can continuously perform the printing within a range in which the remaining amount of the roll paper R remains even when the sensor6detects the near end. The roll paper printer1is provided with a display device (not illustrated), and can display the near end.

When the user visually recognizes the near end display of the display device, the user can continuously perform the printing when the printing is required, such as when customers are lined up for accounting. The user can accommodate new roll paper R in the roll paper printer1at a time when the printing is finished or when the customers stop lining up.

It should be noted that the roll paper printer1may be configured to separately mount a paper detection sensor (not illustrated) that can detect the presence or absence of the paper P on the paper guide4or the protrusion5. The controller can determine whether or not there is no paper P in the roll paper printer1by using the paper detection sensor, and can determine whether or not the printing can be performed. When the sensor6detects the near end and the paper detection sensor detects that there is no paper P, the controller can stop the printing.

The accommodation section12and the cover guide9are configured to guide the roll paper R of which the diameter changes as the paper P is consumed by the printing.

The accommodation section12includes a first accommodation section12a, a second accommodation section12b, the third accommodation section12c, and a fourth accommodation section12d, which are disposed in an order from the up to the down, that is, in an order toward the cover hinge10a. The cover guide9includes a first cover guide9a, a second cover guide9b, and a third cover guide9c, which are disposed in the order from the up to the down, that is, in the order toward the cover hinge10a.

As will be described below, the first accommodation section12aand the first cover guide9asuppress the roll paper R by coming into contact with the roll paper R when the roll paper R that rotates as the paper P is pulled out by the platen3bounces upward or the like.

In addition, when the roll paper printer1is in a posture in which the cover10can be opened upward, that is, in a so-called horizontal placement posture, the second accommodation section12bhaving a recessed shape can stably support the roll paper R.

The roller7is attached to the third cover guide9c, which is a lower portion of the cover guide9. The roller7is located above the cover hinge10a. The roller7can rotate about a shaft7a. As will be described below, the roller7is configured to move in the front-rear direction with respect to the third cover guide9c. When the roller7comes into contact with the roll paper R and is not pressed, the roller7is at a position B0.

The protrusion5is a mechanism that corrects curl of the paper P. The protrusion5is pressed toward the paper guide4by an elastic force of an elastic member for a protrusion (not illustrated), such as a spring. When the protrusion5does not come into contact with the paper P, the protrusion5is at a position M0that protrudes most toward the paper guide4.

2. About Diameter of Roll Paper

2-1. When Roll Paper Has Large Diameter

FIG.3illustrates the roll paper printer1at the time of the printing, in which the roll paper R having an outer diameter D1, which is a first diameter and a large diameter, is accommodated in the accommodation section12. The outer diameter D1is, for example, 83 mm. The roll paper R is at a position C1to which the roll paper R guided by coming into contact with the third accommodation section12cof the accommodation section12and the second cover guide9bof the cover guide9.

The paper P is, for example, long heat sensitive paper. A front surface of the paper P in contact with the head2is coated with a heat sensitive material, and an image can be printed by the head2. A back surface of the paper P is a surface that comes into contact with the platen3.

The roll paper R is wound on a winding core RO such that the front surface of the paper P is on an outside and the back surface is on an inside. As the paper P is wound closer to the winding core RO of the roll paper R, that is, as the paper P is wound closer to a portion in which the outer diameter of the roll paper R is small, the curl is stronger. The outer diameter of the winding core RO is, for example, 18 mm. It should be noted that, in the present embodiment, the outer diameter is also simply referred to as a diameter.

The width of the paper P is, for example, 80 mm. A partition plate (not illustrated) can be inserted into the right of the accommodation section12according to the width of the roll paper R corresponding to the paper P to be used. Due to the partition plate, even the roll paper R having a width smaller than 80 mm, for example, 58 mm, can be stably accommodated on the left and right in the accommodation section12. It should be noted that the partition plate may be insertable into the left of the accommodation section12, or may be insertable into the left or right of the accommodation section12.

The platen3rotates counterclockwise indicated by an arrow by a motor for a platen (not illustrated) to transport the paper P in a transport direction F. In this case, as the paper P is pulled out from the roll paper R by the platen3, the roll paper R also rotates counterclockwise.

From upstream toward downstream in the transport direction F, the accommodation section12, the paper guide4and the protrusion5which face each other, the platen3and the head2which face each other, the cutter14, and the discharge port13are disposed in this order.

The protrusion5and the paper guide4can guide the paper P upstream in the transport direction F of the platen3. The protrusion5can come into contact with the paper P, and can move toward the paper guide4.

With respect to the paper P curled toward the back surface, the protrusion5comes into contact with the paper P from the front surface, and acts to correct the curl of the paper P. The protrusion5can correct the curl by drawing the paper P transported by the platen3, while coming into contact with the front surface of the paper P and bending the paper P.

When the roll paper R has a large diameter as the diameter D1, a load is increased due to the inertia of the roll paper R, and tension of the paper P transported by the platen3is also increased. The protrusion5receives the tension of the paper P, resists the elastic force of the elastic member for the protrusion, and moves in a direction separated from the paper guide4. InFIG.3, the protrusion5is at a position M1that is most separated from the paper guide4.

In the protrusion5at the position M1, an angle of bending the paper P is increased, and an action of correcting the curl is weakened. On the other hand, since the paper P is wound on a portion of the roll paper R having a large diameter, the curl is weak. As described above, the protrusion5corresponds to the paper P having weak curl pulled out from the roll paper R having the diameter D1, and can appropriately correct the curl.

In addition, when the roll paper R rotates, due to a change in a situation of the load of the inertia, the friction between an outer circumference S of the roll paper R and the accommodation section12, or the like due to the forward/rearward movement or the bounce, a load fluctuation may occur. The protrusion5can also alleviate a change in the tension of the paper P due to the load fluctuation while pressing the paper P toward the paper guide4, and advancing and retreating with respect to the paper guide4.

The head2is, for example, a line-type thermal head in which a plurality of heat generating elements are arranged in the left-right direction. The plurality of heat generating elements of the head2can be selected based on print data to generate heat, and can print an image on the paper P, which is the heat sensitive paper.

The platen3and the head2are at positions that face each other with the paper P pulled out from the roll paper R interposed therebetween. The platen3can come into contact with the back surface of the paper P to perform the transportation, and the head2can come into contact with the front surface of the paper P to perform the printing.

The platen3located at a position that faces the head2with the paper P interposed therebetween is also referred to as a platen roller.

The movable blade14aand the stationary blade14bof the cutter14are at positions that face each other with the paper P interposed therebetween. The movable blade14acan move toward the stationary blade14bto cut the paper P between the movable blade14aand the stationary blade14b. The cut paper P is discharged from the discharge port13. It should be noted that the movable blade14amay be mounted on the case11, and the stationary blade14bmay be mounted on the cover10.

The sensor6can come into contact with the outer circumference S of the roll paper R. The sensor6is pressed by the roll paper R having the diameter D1and is at a lower position A1, which is also a position of a surface of the third accommodation section12c. The sensor6can detect that the remaining amount of the roll paper R is sufficient, based on the position A1.

It should be noted that, since the roll paper R having the diameter D1has a large diameter, the roll paper R is at a position C1that does not come into contact with the third cover guide9cand the roller7located below the cover10. The roller7is at the position B0as when the roll paper R is not accommodated in the accommodation section12.

By the way, as described above, when the platen3transports the paper P, the paper P of the roll paper R is also pulled out, and the roll paper R also rotates counterclockwise in the accommodation section12. Along with this rotation, a force for causing the roll paper R to move in the front direction acts on the roll paper R.

The roll paper R is pressed toward the second cover guide9bof the cover guide9by this force. As a result, the outer circumference S of the roll paper R rotates while rubbing the second cover guide9b.

In this case, it may not be possible for the sensor6to detect the remaining amount of the roll paper with high accuracy due to the load of the inertia of the roll paper R, the friction between the outer circumference S of the roll paper R and the second cover guide9b, or the like.

That is, when the load of the inertia of the roll paper R, the friction between the outer circumference S of the roll paper R and the second cover guide9b, or the like is high, the load and the load fluctuation when the platen3transports the paper P are also increased. Therefore, when the platen3transports the paper P, the roll paper R may also move forward and rearward, or bounces upward in some cases. In particular, the platen3is remarkable when the platen3starts transporting the paper P. In this case, when the sensor6moves upward from the position A1, the near end may be erroneously detected. It should be noted that, hereinafter, it is assumed that the load of the friction or the like includes the load based on the inertia of the roll paper R.

The first accommodation section12aand the first cover guide9acan suppress the roll paper R by coming into contact with the roll paper R when the roll paper R that rotates as the paper P is pulled out by the platen3bounces upward or the like.

The cover guide9is made of, for example, a resin, such as polyethylene. On the other hand, in the cover guide9, the second cover guide9b, which is at least a portion of the cover guide9that comes into contact with the outer circumference S of the roll paper R, is covered with, for example, a sheet (not illustrated) containing ultra high molecular weight polyethylene. The sheet containing the ultra high molecular weight polyethylene is also referred to as a so-called low friction sheet.

The ultra high molecular weight polyethylene is obtained by increasing the molecular weight to 1 to 7 million, while the molecular weight of ordinary polyethylene is 20,000 to 300,000. The ultra high molecular weight polyethylene sheet can reduce friction between the material and the material that comes into contact with the material, as compared with the polyethylene cover guide9.

As described above, the cover10has the cover guide9that can guide the roll paper R. The second cover guide9b, which is at least a portion of the cover guide9, is covered with the sheet containing the ultra high molecular weight polyethylene, and has smaller friction with the outer circumference S of the roll paper R than other portions of the cover guide9made of a resin, such as polyethylene.

The second cover guide9b, which is covered with the sheet containing the ultra high molecular weight polyethylene, can reduce the load of the friction with the outer circumference S when the roll paper R rotates. As a result, the load and the load fluctuation when the platen3transports the paper P can be made smaller.

The second cover guide9bcovered with the sheet can suppress the forward/rearward movement or the bounce of the roll paper R when the platen3transports the paper P. By suppressing the forward/rearward or upward movement of the roll paper R, the upward movement of the sensor6from the position A1is also suppressed, and the remaining amount of the roll paper can be detected with higher accuracy.

It should be noted that, instead of the configuration in which the roll paper R having the outer diameter D1comes into contact with the second cover guide9b, a configuration may be adopted in which the roll paper R having the outer diameter D1comes into contact with the first cover guide9aand does not come into contact with the second cover guide9b. In this case, when the cover10is closed, since the first cover guide9ablocks a space above the roll paper R having the outer diameter D1and comes into contact with the roll paper R, the upward bounce of the roll paper R can be suppressed. In this case, the first cover guide9amay be covered with the sheet containing the ultra high molecular weight polyethylene.

2-2. When Roll Paper Has Medium Diameter

The paper P is printed and consumed, and the roll paper R becomes the roll paper R having a diameter D2, which is a second diameter, is a medium diameter, and is smaller than the diameter D1which is a large diameter. The diameter D2is, for example, 60 mm.FIG.4illustrates the roll paper printer1at the time of the printing, in which the roll paper R having the diameter D2is accommodated in the accommodation section12.

The roll paper R is at a position C2to which the roll paper R guided by coming into contact with the third accommodation section12cof the accommodation section12and the third cover guide9cof the cover guide9. Also, the position of the winding core RO, which is a position of the center of gravity of the roll paper R having the diameter D2, moves in the front-down direction as compared to when the roll paper R has the diameter D1.

When the roll paper R has the diameter D2, a distal end of the sensor6comes into contact with the outer circumference S of the roll paper R, and the sensor6is at a position A2which is lower than the position A1when the roll paper R has the diameter D1. The sensor6can continuously detect that the remaining amount of the roll paper R is sufficient, based on the position A2.

As described above, when the roll paper R rotates in the accommodation section12, a force for causing the roll paper R to move to the third cover guide9cin the front direction acts on the roll paper R.

The roll paper R having the diameter D2is at the position C2, and the outer circumference S comes into contact with the roller7mounted on the third cover guide9c. In this case, the roller7is at the position B0.

The roller7can rotate smoothly while coming into contact with the outer circumference S of the roll paper R. The rotating roller7can reduce the load of the friction or the like when the roll paper R rotates. As a result, the load and the load fluctuation when the platen3transports the paper P can be made smaller.

The roller7can suppress the forward/rearward movement or the bounce of the roll paper R. By suppressing the forward/rearward or upward movement of the roll paper R, the upward movement of the sensor6from the position A2is also suppressed, and the remaining amount of the roll paper can be detected with higher accuracy.

The tension of the paper P is smaller when the roll paper R has the smaller diameter D2than when the roll paper R has the diameter D1. As a result, the protrusion5further moves toward the paper guide4and moves from the position M1to a position M2due to the reduced tension of the paper P.

The protrusion5at the position M2has a smaller angle of bending the paper P than the protrusion5at the position M1, and has a stronger action of correcting the curl. On the other hand, since the paper P is wound on a portion of the roll paper R having a medium diameter, the curl is stronger. As described above, the protrusion5corresponds to the paper P having stronger curl pulled out from the roll paper R having the diameter D2, and can appropriately correct the curl.

In addition, also in this case, the protrusion5can alleviate a change in the tension of the paper P due to the load fluctuation while pressing the paper P toward the paper guide4, and advancing and retreating with respect to the paper guide4.

2-3. When Roll Paper Has Small Diameter

When the paper P is printed and further consumed, the roll paper R becomes the roll paper R having a diameter D3, which is even smaller than the diameter D2as a medium diameter, is a third diameter, and is a small diameter. The diameter D3is, for example, 30 mm.FIG.5illustrates the roll paper printer1at the time of a standby, in which the roll paper R having the diameter D3is accommodated in the accommodation section12and is not printed. On the other hand,FIG.6illustrates the roll paper printer1when printing the roll paper R having the diameter D3.

First, the roll paper printer1at the time of the standby ofFIG.5will be described. The platen3does not transport the paper P, and the roll paper R does not rotate. Therefore, a force for causing the roll paper R to move in the front direction does not act on the roll paper R.

The roll paper R is at a position C3to which the roll paper R guided by coming into contact with the fourth accommodation section12dof the accommodation section12and the roller7of the third cover guide9cof the cover guide9. In particular, a rear side of the roll paper R is guided by a rear edge of the fourth accommodation section12dhaving a recessed shape. The roll paper R is interposed between the roller7and the rear edge of the fourth accommodation section12d. Also, the position of the winding core RO, which is a position of the center of gravity of the roll paper R having the diameter D3, further moves in the front-down direction as compared to when the roll paper R has the diameter D2.

When the roll paper R has the diameter D3, the sensor6comes into contact with the outer circumference S of the roll paper R, and the sensor6is at a position A3which is higher than the position A2when the roll paper R has the diameter D2. The sensor6can continuously detect that the remaining amount of the roll paper R is sufficient, based on the position A3.

The outer circumference S of the roll paper R is in a state of coming into contact with the roller7of the third cover guide9c. Here, since the force for causing the roll paper R to move in the front direction does not act on the roll paper R, the roll paper R does not press the roller7in the front direction. In this case, since the roller7is not pressed, the roller7is at the position B0. The outer circumference S of the roll paper R does not come into contact with the third cover guide9c.

Next, the roll paper printer1at the time of the printing ofFIG.6will be described. The roll paper R is at a position C4to which the roll paper R guided by coming into contact with the fourth accommodation section12dof the accommodation section12and the roller7of the third cover guide9cof the cover guide9. Also, the position of the winding core RO, which is a position of the center of gravity of the roll paper R at the time of the printing, also moves in the front-down direction as compared to the time of the standby.

At the time of the printing, the sensor6comes into contact with the outer circumference S of the roll paper R, and is at a position A4which is higher than the position A3at the time of the standby. The sensor6can detect that the remaining amount of the roll paper R is sufficient, based on the position A4.

Since the platen3transports the paper P at the time of the printing, the roll paper R rotates in the accommodation section12. As described above, the force for causing the roll paper R to move in the front direction acts on the roll paper R. The roll paper R having the diameter D3has the outer circumference S that comes into contact with the roller7, and moves to further press the roller7in the front direction. The roller7is pressed by the roll paper R, and moves forward from the position B0to a position B1.

The roller7can rotate smoothly while being pressed by the roll paper R and moving from the position B0to the position B1while coming into contact with the outer circumference S of the roll paper R. The roller7that rotates can reduce the load of the friction or the like when the roll paper R rotates, and can suppress the load and the load fluctuation when the platen3transports the paper P.

Then, by suppressing the forward/rearward or upward movement of the roll paper R, the upward movement of the sensor6from the position A4is also suppressed, and the remaining amount of the roll paper can be detected with higher accuracy.

By the way, the sensor6comes into contact with the outer circumference S of the roll paper R that rotates. A portion in which the sensor6comes into contact with the outer circumference S of the roll paper R is referred to as a contacting point. In the example ofFIG.6, the distal end of the sensor6comes into contact with the outer circumference S of the roll paper R, and the contacting point serves as the distal end of the sensor6. When the platen3transports the paper P and the roll paper R rotates in the accommodation section12, the roll paper R is interposed between the contacting point and a portion that faces the position of the contacting point.

When it is supposed that the third cover guide9cdoes not have the roller7, the portion that faces the position of the contacting point serves as a portion in which the roll paper R directly comes into contact with the third cover guide9c. When the roll paper R attempts to rotate, high friction is generated with the third cover guide9c. This load of the friction acts as moment of force, and acts at the contacting point that is the position that faces the portion in which the roll paper R comes into contact with the third cover guide9c, such that the roll paper R bites into the distal end of the sensor6.

This action can be a factor that causes a large load and a large load fluctuation with respect to the transportation of the paper P by the platen3. As a result, the roll paper R may move forward and rearward or upward, and the sensor6may also move upward from the position A4, which may result in the erroneous detection of the near end.

In addition, in this case, when the roll paper R is pulled in the transport direction F along with the transportation of the paper P by the platen3, the distal end of the sensor6may also be pulled in the transport direction F in a state in which the distal end of the sensor6also bites into the roll paper R. When the sensor6is pulled in the transport direction F and is at the position A0which is higher than the position A4, the near end is erroneously detected.

In the embodiment, the roller7is disposed at a position that faces the position of the contacting point with the roll paper R interposed therebetween. The roller7can rotate smoothly while coming into contact with the outer circumference S of the roll paper R. The roller7that rotates can suppress the biting of the distal end of the sensor6into the roll paper R, and can reduce the load of the friction or the like when the roll paper R rotates. As a result, the load and the load fluctuation when the platen3transports the paper P can be made smaller.

It should be noted that the position of the roller7does not have to be a position at which an angle formed with the position of the contacting point is 180 degrees with the winding core RO of the roll paper R as the center. This angle may be in a range of 150 degrees to 210 degrees.

In addition, even when it is supposed that the distal end of the sensor6is in a state of biting into the roll paper R, the roller7can rotate together with the roll paper R when the roll paper R is pulled in the transport direction F.

Further, the roller7can move from the position B0toward the position B1, that is, in the front direction and is a direction intersecting the transport direction F. It is possible to alleviate the biting of the distal end of the sensor6into the roll paper R.

As described above, the roller7at the position that faces the position of the contacting point with the roll paper R interposed therebetween can suppress the forward/rearward or upward movement of the roll paper R or the upward movement of the sensor6due to pulling. As a result, the sensor6can detect the remaining amount of the roll paper with higher accuracy.

It should be noted that, in the above description, the example is described in which the roller7is mounted on the cover guide9of the cover10. The roller7need only be at the position that faces the position of the contacting point with the roll paper R interposed therebetween, and may be mounted on, for example, the fourth accommodation section12dor the case11extending upward from the lower front.

It should be noted that, at the time of the printing, the outer circumference S of the roll paper R may also come into contact with the third cover guide9cin addition to the roller7. In the third cover guide9cas well, a portion of the roll paper R that comes into contact with the outer circumference S may be covered with the sheet containing the ultra high molecular weight polyethylene. The third cover guide9cthat is covered with the sheet can reduce the load of the friction when the roll paper R rotates.

The tension of the paper P is smaller when the roll paper R has the smaller diameter D3than when the roll paper R has the diameter D2. As a result, the protrusion5further moves toward the paper guide4and moves from the position M2to a position M3due to the reduced tension of the paper P.

In the protrusion5at the position M3, as compared to the protrusion5at the position M2, an angle of bending the paper P is even smaller, and an action of correcting the curl is even stronger. On the other hand, since the paper P is wound on a portion of the roll paper R having an even smaller diameter, the curl is even stronger. As described above, the protrusion5corresponds to the paper P having even stronger curl pulled out from the roll paper R having the diameter D3, and can appropriately correct the curl.

In addition, also in this case, the protrusion5can alleviate the change in the tension of the paper P due to the load fluctuation while pressing the paper P toward the paper guide4, and advancing and retreating with respect to the paper guide4.

Here, the roller7will be specifically described with reference toFIG.7.FIG.7illustrates an embodiment in which a plurality of rollers in which a roller8is added to the roller7are provided. The roller7and the roller8have the same configuration, and thus the roller7will be mainly described.

The roller7is made of a resin, such as plastic, and is formed into a cylindrical shape. The roller7includes the shaft7a. The roller7is fixed by passing the shaft7athrough the center of the cylinder.

A support section97that supports the roller7is formed in the third cover guide9cof the cover guide9. The support section97includes a bearing97aand an opening97b. The bearing97arotatably supports the shaft7a. The roller7can move in the front-rear direction through the opening97b.

The shaft7ais an elastic member having the elastic force, and can be elastically deformed in the front-rear direction. The shaft7ais formed in a shaft shape by using, for example, a spring steel material, such as carbon steel or alloy steel.

The roller7can press the roll paper R in the rear direction by the elastic force of the shaft7a. When the shaft7ais pressed by the roll paper R, the shaft7acan be elastically deformed in the front direction while pressing the roll paper R in the rear direction.

As described above, the roller7is rotatably supported by the cover10by the shaft7ahaving the elastic force, and can move while elastically deforming the shaft7a.

The roller8has the same configuration as the roller7. The roller8includes a shaft8a. A support section98that supports the roller8is formed in the third cover guide9cof the cover guide9. The support section98includes a bearing98aand an opening98b.

The roller7and the roller8are arranged in the left-right direction, which is the width direction of the roll paper R, and are attached to the third cover guide9c. The roller7disposed on the right and the roller8disposed on the left can rotate and can move while pressing the roll paper R in a well-balanced manner in the left-right direction.

For example, when the roll paper R has the maximum width W that can be accommodated in the accommodation section12, the roll paper R comes into contact with the roller7and the roller8. The roll paper R having the width W can move in the front-rear direction in a well-balanced manner in the left-right direction while receiving the elastic force from the roller7and the roller8. The maximum width W of the roll paper R is, for example, 80 mm.

It should be noted that, when the roll paper R has the minimum width W1, the roll paper R may come into contact with only one roller8. The roll paper R can move in the front-rear direction in a well-balanced manner in the left-right direction while receiving the elastic force from the roller8. The minimum width W1of the roll paper R is, for example, 58 mm. In addition, when the diameter of the roll paper R having the minimum width W1is smaller and lighter, two elastic forces of the roller7and the roller8act, and thus the roll paper R may bounce depending on the behavior of the roll paper R in the accommodation section12. When the roll paper R comes into contact with only one roller8, since only one elastic force acts, it is possible to suppress the bounce of the roll paper R.

As described above, the roller8, which is at least a portion of the plurality of rollers7and8, can come into contact with the outer circumference S of the roll paper R having the minimum width W1that can be accommodated in the accommodation section12.

It should be noted that the roller7need only be the contact member that can come into contact with the roll paper R and can move, and may be configured not to rotate. A surface of the contact member that comes into contact with the roll paper R may be, for example, formed in a cylindrical shape, an elliptical column shape, or a smooth protrusion shape. In this case, instead of the shaft7a, a spring, rubber, or the like that can be elastically deformed and can move in the front-rear direction while pressing the contact member may be used for configuration. The contact member may be formed of a resin, such as plastic, and may have a front surface covered with the sheet containing the ultra high molecular weight polyethylene.

The roll paper printer1is configured as a so-called left reference, which performs the accommodation in the accommodation section12with reference to the left of the roll paper R and performs the transportation and the printing with reference to the left of the roll paper R. When the roll paper R having the width W1smaller than the width W, the roll paper R is accommodated such that the left end of the roll paper R comes into contact with the accommodation section12and the right end of the roll paper R comes into contact with the partition plate inserted into the accommodation section12.

The controller sets a print area corresponding to the width of the roll paper R to be used, with reference to the left of the roll paper R, and controls the head2to perform the printing within a range of the print area. As a result, the head2does not extend beyond the minimum width W1of the roll paper R, for example, to perform the printing.

As illustrated inFIG.1, in order to detect the remaining amount of the roll paper R accommodated on the left side of the accommodation section12, the sensor6is disposed on the left inside the accommodation section12. Even when the roll paper R has the minimum width W1, the sensor6disposed on the left side can come into contact with the roll paper R accommodated on the left side. Moreover, the roller8disposed on the left side can come into contact with the roll paper R having the minimum width W1.

It should be noted that, when the roll paper printer1is configured with reference to the right, the positional relationship described above is reversed left and right.

In addition, in the above description, two examples of the roller7and the roller8is described. In this case, the plurality of rollers including the roller7and the roller8are mounted on the cover10, and are arranged in the width direction of the roll paper R. The number of the rollers may be two or more when corresponding to the roll paper R having a plurality of types of widths, and may be one when corresponding to only one type of width. The plurality of rollers including the roller7and the roller8are mounted on the cover10, and are arranged in the width direction of the roll paper R.

2-4. When Roll Paper Is At Near End

When the paper P is printed and further consumed, the roll paper R becomes the roll paper R having a diameter D4, which is even smaller than the diameter D3as a small diameter and is a fourth diameter, and at which the near end is detected by the sensor6. The diameter D4is, for example, 20 mm.FIG.8illustrates the roll paper printer1at the time of the printing, in which the roll paper R having the diameter D4is accommodated in the accommodation section12.

The roll paper R disengages from the roller7and the rear edge of the fourth accommodation section12d, and is at a position C5to which the roll paper R is guided by coming into contact with the inside of the fourth accommodation section12dof the accommodation section12. Also, the position of the winding core RO, which is a position of the center of gravity of the roll paper R having the diameter D4, moves in the front-down direction as compared to when the roll paper R has the diameter D3.

The fourth accommodation section12dhaving a recessed shape can stably support the roll paper R from below. The roller7disengages from coming into contact with the roll paper R, and is at the position B0.

When the roll paper R becomes to have the diameter D4, the sensor6is disengaged from coming into contact with the outer circumference S of the roll paper R, and is at the highest position A0. The sensor6can detect the near end when the sensor6is at the position A0. The controller can display the near end by the display device. The position A0of the sensor6is the same as the position when the roll paper R is not accommodated in the accommodation section12.

The user can visually recognize the display of the near end of the display device, and can accommodate the new roll paper R in the accommodation section12. It should be noted that, even when the near end is detected, the roll paper printer1can also continuously perform the printing within the range in which the remaining amount of the roll paper R remains.

As described above, when the platen3transports the paper P, the paper P of the roll paper R is also pulled out, and the roll paper R also rotates counterclockwise in the accommodation section12. In this case, a force for causing the roll paper R to move in the front direction acts on the roll paper R.

However, the roll paper R is stably supported by the fourth accommodation section12dhaving a recessed shape so as not to move in the front direction.

Even when it is supposed that the roll paper R moves in the front direction, the roll paper R can come into contact with the roller7. The roller7can rotate smoothly while being pressed by the roll paper R and moving from the position B0to the position B1while coming into contact with the outer circumference S of the roll paper R.

In this case, the rotating roller7can reduce the load of the friction or the like when the roll paper R rotates. As a result, the load and the load fluctuation when the platen3transports the paper P can be made smaller.

It should be noted that, even in this case as well, the sensor6is at the position A0, and a state in which the roll paper R disengages from coming into contact with the outer circumference S can be maintained. The sensor6can continuously detect the near end.

The tension of the paper P is smaller when the roll paper R has the smaller diameter D4than when the roll paper R has the diameter D3. As a result, the protrusion5further moves toward the paper guide4and moves from the position M3to a position M4due to the reduced tension of the paper P.

In the protrusion5at the position M4, as compared to the protrusion5at the position M3, an angle of bending the paper P is even smaller, and an action of correcting the curl is even stronger. On the other hand, since the paper P is wound on a portion of the roll paper R having an even smaller diameter, the curl is even stronger. As described above, the protrusion5corresponds to the paper P having even stronger curl pulled out from the roll paper R having the diameter D4, and can appropriately correct the curl.

In addition, also in this case, the protrusion5can alleviate the change in the tension of the paper P due to the load fluctuation while pressing the paper P toward the paper guide4, and advancing and retreating with respect to the paper guide4.

3. Accommodation of Roll Paper R

FIGS.9and10illustrate sectional views of the roll paper printer1in a state in which the cover10is opened forward.

FIG.9illustrates a state in which the roll paper printer1does not have the roll paper R. The roller7is mounted on the third cover guide9cof the cover guide9. The roller7is movably supported by the shaft7ahaving the elastic force. Since the roller7does not come into contact with the roll paper R, the roller7is at the position B0, which is a position before the roller7moves.

FIG.10illustrates a state in which the roll paper R is mounted on the cover guide9of the cover10opened forward by the user who attempts to accommodate the roll paper R in the accommodation section12. The roller7is pressed by the roll paper R, and moves from the position B0to the position B1.

In both cases ofFIGS.9and10, since the protrusion5mounted on the case11does not come into contact with the paper P, the protrusion5is at the position M0that protrudes most.

The cover10is opened forward at an angle close to 90 degrees with respect to the case11, and the accommodation section12is sufficiently opened.

When the roll paper R is accommodated in the accommodation section12, the user need only mount the roll paper R on the cover guide9of the cover10opened forward. Then, the user can easily accommodate the roll paper R mounted on the cover guide9in the accommodation section12by simply rolling or sliding the roll paper R toward the accommodation section12on the rear side.

It should be noted that, since there is no roll paper R in the accommodation section12, the sensor6is at the position A0advanced upward.

As described above, the protrusion5is at the position M0that protrudes most, but when the user accommodates the roll paper R in the accommodation section12, the protrusion5does not get in the way. That is, it is not necessary for the user to lift the roll paper R and accommodate the roll paper R in the accommodation section12, and there is no possibility that the user's finger or the roll paper R touch the protrusion5.

Further, the cover10is opened forward, and the accommodation section12is sufficiently opened. The user can easily accommodate the roll paper R in the opened accommodation section12without the protrusion5getting in the way.

The cover guide9is configured to guide the roll paper R while supporting the roll paper R such that the roll paper R is rolled or slid toward the accommodation section12when the user accommodates the roll paper R in the accommodation section12. The configuration in which the cover guide9guides the roll paper R will be specifically described.

The cover guide9includes the first cover guide9a, the second cover guide9b, and the third cover guide9c, which are disposed in the order toward the cover hinge10a, that is, in the order toward the accommodation section12in a state in which the cover10is opened.

As described above, when the cover10is closed, the first cover guide9aand the second cover guide9bcan come into contact with the roll paper R having the first diameter D1, which is a large diameter, including when the roll paper R bounces. Meanwhile, the third cover guide9cdoes not come into contact with the roll paper R having the first diameter D1.

Meanwhile, when the cover10is opened, the first cover guide9ais in a posture of being inclined downward toward the accommodation section12. Stated another way, the first cover guide9ais inclined toward the lower right on the paper surface ofFIG.9.

The first cover guide9acan guide the roll paper R having the first diameter D1toward the accommodation section12via the second cover guide9band the third cover guide9calong this inclination. That is, the roll paper R mounted on the first cover guide9acan easily roll toward the accommodation section12along the first cover guide9a.

The user can easily accommodate the roll paper R by rolling the roll paper R down to the accommodation section12by the downward inclination of the first cover guide9atoward the accommodation section12.

As described above, at least the second cover guide9bis covered with the sheet containing the ultra high molecular weight polyethylene, and is configured to have smaller friction with the roll paper R other portions of the cover guide9.

With such a sheet, the second cover guide9bcan reduce the friction with the roll paper R. The second cover guide9bcan guide the roll paper R having the first diameter D1toward the accommodation section12via the third cover guide9c. In this case, the roll paper R mounted on the second cover guide9bcan move toward the accommodation section12while sliding along the second cover guide9b.

The user can slide and roll the roll paper R down to the accommodation section12by the sheet that covers the second cover guide9bfor reducing the friction, and can easily accommodate the roll paper R.

It should be noted that, in the embodiment, when the cover10is opened, the second cover guide9bis not inclined downward toward the accommodation section12, but may be inclined. The roll paper R is more easily rolled or easily slid.

In addition, in the embodiment, the first cover guide9aand the third cover guide9care not covered with the sheet containing the ultra high molecular weight polyethylene, but at least a portion of the first cover guide9aand the third cover guide9cmay be covered with this sheet. The roll paper R is more easily rolled or easily slid, and can move toward the accommodation section12.

When the cover10is opened, the third cover guide9cis in a posture of being inclined downward toward the accommodation section12. Stated another way, the third cover guide9cis inclined toward the lower right on the paper surface ofFIG.9.

The third cover guide9ccan guide the roll paper R having the first diameter D1toward the accommodation section12along this inclination. The roll paper R mounted on the third cover guide9ccan easily roll toward the accommodation section12along the third cover guide9c.

The user can roll the roll paper R down to the accommodation section12by the downward inclination of the third cover guide9ctoward the accommodation section12, and can easily accommodate the roll paper R.

In addition, the third cover guide9cis inclined downward toward the accommodation section12, so that an opening of the accommodation section12can be widened. Since the opening of the accommodation section12is widened, the user easily accommodates the roll paper R having the first diameter D1.

In particular, even when the protrusion5is at the position M0that protrudes most from the case11, since the opening of the accommodation section12is wide, the user easily accommodates the roll paper R having the first diameter D1without the protrusion5getting in the way. In other words, even when the protrusion5moves in a direction in which the opening of the accommodation section12is narrowed and the protrusion5is at the position M0that protrudes most, since the third cover guide9cis inclined downward toward the accommodation section12, that is, in a direction in which the opening of the accommodation section12is widened, the user easily accommodates the roll paper R having the first diameter D1without the protrusion5getting in the way.

It should be noted that the direction in which the opening of the accommodation section12is narrowed, which is a movement direction of the protrusion5, is, for example, a direction in which the protrusion5moves toward the paper guide4, but may be a direction from the inside to the outside of the case.

Further, as described above, the roller7is rotatably and movably mounted on the third cover guide9cby the shaft7ahaving the elastic force. As illustrated inFIG.10, in a state in which the roller7is pressed by the roll paper R mounted on the third cover guide9cand moves from the position B0to the position B1, the roller7can rotate smoothly while coming into contact with the outer circumference S of the roll paper R.

In the above description, the example of the roller7is described, but the same applies to the roller8illustrated inFIG.7. Further, the same applies to when the plurality of rollers are mounted on the third cover guide9c.

As described above, the roll paper printer1according to the present embodiment includes the case11including the accommodation section12that can accommodate the roll paper R, and the cover10that can rotate about the cover hinge10alocated below the case, and opens and closes the accommodation section12, the paper guide4that can guide paper P, and the protrusion5that can come into contact with the paper, and can move toward the paper guide4.

The cover10includes the cover guide9that can guide the roll paper R, and the cover guide9include the first cover guide9a, the second cover guide9b, and the third cover guide9cdisposed in this order toward the cover hinge10a.

When the cover10is closed, the first cover guide9aand the second cover guide9bcan come into contact with the roll paper R having the first diameter D1. In this case, the third cover guide9cdoes not come into contact with the roll paper R having the first diameter D1.

Meanwhile, when the cover10is opened, the third cover guide9cis inclined downward toward the accommodation section12, and can mount the roll paper R having the first diameter D1and guide the roll paper R to the accommodation section12.

With the roll paper printer1having such a configuration, when the cover10is opened, the accommodation section12is sufficiently opened. Even when the protrusion5is at the position M0that most protrudes from the case11, the user can easily accommodate the roll paper R having the first diameter D1in the accommodation section12without the protrusion5getting in the way.

Further, the user can roll the roll paper R down to the accommodation section12by the downward inclination of the third cover guide9ctoward the accommodation section12, and can easily accommodate the roll paper R. The inclination of the third cover guide9calso has an effect of widening the opening of the accommodation section12.

As described above, although the present embodiment is described with reference to the drawings, a specific configuration is not limited to the embodiment, and may be changed, replaced, deleted, or the like without departing from the gist of the present disclosure.

For example, in the above description, the head2is described with an example of the thermal head, but the printing method does not matter. For example, the head2may be an ink jet head. In this case, since the ink jet head cannot come into contact with the platen3and interpose the paper P, a driven roller that faces the platen3and interposes the paper P need only be mounted on the case11.

In the above description, the roller7is made of a resin, such as plastic, but may be made of rubber or metal.

In addition, the surface of the paper P that comes into contact with the roller7does not have to be the surface for the printing. The roll paper R is wound such that the surface for printing the paper P is on the inside. In this case, the positions of the head2and the platen3are opposite to the positions illustrated in the drawings described above.

When the roll paper R is smaller than the diameter D1, which is a large diameter, the third cover guide9cmay be made to function as a guide that suppress the roll paper R that rotates as the paper P is pulled out by the platen3by coming into contact with the roll paper R when the roll paper R bounces upward or the like. The sensor6is pressed upward by the elastic member, and the roll paper R becomes lighter as the paper P is pulled out. Therefore, in particular, when the roll paper R has the diameter D3and the distal end of the sensor6comes into contact with the outer circumference S of the roll paper R, the roll paper R is likely to bounce upward. For example, when the roll paper R has the diameter D3, by making the third cover guide9cfunction as a guide that covers the upper side of the outer circumference S of the roll paper R, the third cover guide9ccan suppress the roll paper R by coming into contact with the roll paper R when the roll paper R bounces upward.