JP5747624B2 - Printing medium supply mechanism and printing apparatus - Google Patents

Description

  The present invention relates to a print medium supply mechanism and a printing apparatus.

2. Description of the Related Art Conventionally, there is known a printer including a roll paper having a configuration in which a long recording paper is used as a printing medium and the recording paper is wound into a roll (see, for example, Patent Documents 1 and 2). Such printers are often used as printing means for business equipment such as POS terminals and automatic teller machines (ATMs). Hereinafter, a printer using roll paper as a print medium may be referred to as a “roll paper printer”.

In addition to the printing unit that prints on the recording paper, the roll paper printer includes a transport unit that transports the recording paper while pulling out the recording paper from the roll paper. As such a printer, a configuration in which a recording sheet is pulled out by a platen (conveying means) driven mainly by a motor, conveyed to a printing means downstream in the conveying direction, and discharged as a printed matter while being sequentially printed by the printing means can be exemplified. .

Japanese Patent Laid-Open No. 5-301403 JP 2002-356252 A

When such a printer is employed for business equipment, roll paper having a large winding radius may be used in order to reduce the frequency of replenishment and replacement of roll paper and enable long-term use.
However, when roll paper with a large winding diameter is used, since the inertia force of the roll paper is large, a large force is required to rotate and pull out the roll paper. Sometimes the recording paper cannot be pulled out in a timely manner.

In a roll paper printer, paper is fed at a constant speed and printing is performed by a printing unit that intersects the paper feed direction. Therefore, if the paper feed speed varies, there is a risk of printing failure. Therefore, when roll paper having a large winding diameter is used as described above, there is a risk of printing failure at the start of printing.

On the other hand, for example, it is conceivable to increase the capacity of the motor that constitutes the conveyance means, but this may lead to an increase in power consumption and an increase in the size of the apparatus, and thus may not be an appropriate solution in product design. is there. Therefore, there has been a demand for a technique capable of reducing the load during drawing with a simple configuration.

In addition to the printer using roll paper, the above-described problem can occur in the same manner when printing is performed while holding a belt-shaped print medium other than roll paper wound in a cylindrical shape and pulling it out.

The present invention has been made in view of such circumstances, and reduces the inertia load when starting to draw out a printing medium wound up into a cylindrical shape like roll paper, and transports the printing medium at the start of printing. An object of the present invention is to provide a printing medium supply mechanism capable of suppressing delay. It is another object of the present invention to provide a printing apparatus that has such a print medium supply mechanism and suppresses printing defects.

In order to solve the above-described problem, a printing medium supply mechanism according to the present invention is inserted through the winding center of a belt-shaped printing medium wound in a cylindrical shape, and a rotation shaft that rotatably supports the printing medium; A rotating portion that supports the rotating shaft, and the rotating portion is a rotating shaft set in a position different from the extending direction of the rotating shaft and parallel to the extending direction of the rotating shaft. The rotation distance between the rotation shaft and the rotation shaft is shorter as the remaining amount of the print medium is smaller.

When an attempt is made to pull out the print medium, a force in a direction in which the print medium is rotated so as to pull out the print medium is applied to the print medium wound in a cylindrical shape. At the same time, a force in the direction of rotating the rotation member about the rotation axis is also applied to the rotation member that supports the print medium via the print medium.

Then, the printing medium rotates in the paper feeding direction simultaneously with the rotating member. As a result, even if the recording paper is not pulled out from the roll paper, the recording paper is conveyed without being delayed by the printing on the thermal head. Is called.

Further, while the roll paper rotates, the roll paper starts to rotate, and the recording paper is pulled out from the roll paper.

The movement of the drawn print medium by the rotation of the whole cylindrical print medium and the movement of the drawn print medium by the rotation of the whole cylindrical print medium act in cooperation. As a result, the inertial load when starting to pull out the print medium is reduced.

Therefore, according to this configuration, it is possible to provide a print medium supply mechanism that hardly causes a delay in transport of the print medium at the start of printing. Furthermore, according to this configuration, as the force (dynamic load) necessary for rotating the print medium around the rotation axis or rotating around the rotation axis decreases, the rotation axis and the rotation axis Therefore, the torque applied to the cylindrical print medium when the print medium is pulled is also reduced. Therefore, even if the remaining amount of the cylindrical print medium changes, an excessively large force is not applied to the print medium, and the print medium is less likely to be slack.

In the present invention, the rotating unit includes a pair of rotating members that sandwich the print medium and that are rotatably provided around the rotating shaft, and the rotating shaft includes the pair of rotating members. It is desirable to be provided across the moving member.
According to this configuration, since the load of the print medium is distributed and applied to the pair of rotating members, the load applied to the rotating shaft portion of the rotating member can be dispersed and damage can be suppressed.

In the present invention, it is desirable that the rotating portion includes a connecting member that connects the pair of rotating members to each other .

According to this configuration, since the movements of the pair of rotating members are synchronized via the connecting member, the rotating member can be easily rotated. Therefore, it is possible to easily reduce the inertial load when starting to pull out the print medium.

In the present invention, it is preferable that the printing medium is a roll paper on which a belt-like recording paper is wound.
According to this configuration, even when a roll paper having a large winding radius is supported, a conveyance delay at the start of printing can be suppressed.

Further, the printing apparatus of the present invention includes the above-described print medium supply mechanism, a conveyance unit that pulls out and conveys the belt-shaped print medium wound in a cylindrical shape, which is held by the print medium supply mechanism, and the drawn-out Printing means for printing on a print medium.
According to this configuration, it is possible to provide a printing apparatus that suppresses printing defects at the start of printing.

1 is a schematic perspective view of a printer having a print medium supply mechanism of a first embodiment. 1 is a cross-sectional view of a printer having a print medium supply mechanism of a first embodiment. It is explanatory drawing of the function of the printing medium supply mechanism which concerns on 1st Embodiment. It is a schematic perspective view which shows the modification of a printing medium supply mechanism. It is sectional drawing of the printer which has the printing medium supply mechanism of 2nd Embodiment. It is a graph which shows the result of an Example.

[First Embodiment]
The print medium supply mechanism and printer (printing apparatus) according to the first embodiment of the present invention will be described below with reference to FIGS. In all the drawings below, the dimensions and ratios of the constituent elements are appropriately changed in order to make the drawings easy to see.

1 and 2 are explanatory diagrams of a printer (printing apparatus) having a print medium supply mechanism of the present embodiment, FIG. 1 is a schematic perspective view, and FIG. 2 is a cross-sectional view taken along line XX in FIG. It is. In the present embodiment, the printer is described as being a thermal printer that employs a thermal coloring method using thermal paper as a print medium.

As shown in FIG. 1, the printer 1 of this embodiment is a roll paper printer that uses a roll paper R obtained by winding a recording paper S into a cylindrical shape as a print medium. Printer 1 is roll paper R
A supply unit (printing medium supply mechanism) 10 for supporting and supplying the sheet, a printing unit 20 for printing on the recording paper S drawn from the roll paper R, and a box-shaped frame 30 having an opening on the upper side. ing. The supply unit 10 and the printing unit 20 are fixed to the frame 30.

The supply unit 10 is supported by a pair of support legs 11 fixed to both sides of the frame 30. The printing unit 20 is supported by a pair of support legs 29 fixed on both sides of the frame 30, and is disposed so as to face the roll paper R supported by the supply unit 10 above the frame 30. Yes.

The recording paper S has a printing surface composed of a coloring layer in which a coloring agent is held by a binder or the like. The roll paper R is obtained by winding the recording paper S into a cylindrical shape with the printing surface as the outer surface.

In such a printer 1, first, the recording paper S is transferred from the roll paper R arranged in the supply unit 10.
Is pulled out, and the drawn recording paper S is inserted into the inside of the printing unit 20 facing the roll paper R from an insertion port (not shown). The recording sheet S printed inside the printing unit 20 is discharged from the discharge port B and cut by the cutting unit 24 provided at the discharge port B. The printer 1 generally operates in this way.

Next, each configuration of the printer 1 will be described in more detail along the paper feeding direction of the recording paper S with reference to FIG.

The supply unit (printing medium supply mechanism) 10 connects a pair of rotating members 12 provided facing the roll paper R to each of the pair of support legs 11, and connects the rotation members 12 to the support legs 11. A rotation shaft 13 that is movably supported, a rotation shaft 14 that is inserted into the roll paper R and that rotatably supports the roll paper R, and the pair of rotation members 12 are provided. And a bearing portion 15 for supporting the rotating shaft 14 spanned therebetween. The rotating shaft 13 is the rotating shaft 1
4 is set in a position parallel to the extending direction of 4 and different from the extension axis of the rotating shaft 14. In addition, a pair of rotation member 12 corresponds to the rotation part of this invention.

About each structure of the supply part 10, unless the function is impaired, various formation materials and various structures can be employ | adopted. For example, the supporting foot 11, the rotating member 12, and the rotating shaft 14 may be formed using various forming materials such as a resin material and a metal material as long as the supporting foot 11, the rotating member 12, and the rotating shaft 14 have rigidity enough to prevent deformation due to the load of the roll paper R. Can do. Further, the rotating shaft 13 and the rotating shaft 14 are used.
For the purpose of assisting the rotating or rotating operation, a configuration that suppresses friction such as a bearing can be adopted as necessary.

The printing unit 20 includes a casing 21, a thermal head (printing unit) 22 provided in the casing 21 in the conveyance path of the recording paper S, and a platen (facing the thermal head 22). (Conveying means) 23 and a cutting unit 24 for cutting the printed recording paper S every predetermined printing unit. The recording paper S drawn out from the supply unit 10 is inserted into the printing unit 20 through the insertion port A of the printing unit 20 disposed opposite to the printing unit 20, printed by the thermal head 22, and then downstream of the conveyance path of the recording paper S. The cutting unit 24 provided near the discharge port B is cut for each printing unit.

The thermal head 22 has a plurality of heating elements for printing on the recording paper S. The heating elements arranged in the thermal head 22 selectively generate heat when energized, and this thermal energy selectively reacts with the color former contained in the recording paper S, so that various types of heat are generated on the printing surface of the recording paper S. Print information. The thermal head 22 is urged in the direction of the platen 23 and sandwiches the recording paper S between the thermal head 22 and the platen 23.

The platen 23 is formed in a cylindrical roller shape by an elastic member such as rubber and is rotatably supported. Further, the platen 23 is provided with a motor (not shown) for rotating the platen 23 to rotate the platen 23. Therefore, when the platen 23 rotates, the recording paper S is transported downstream of the transport path.

The cutting unit 24 includes a movable blade 241 and a fixed blade 242 that are disposed to face each other with the discharge port B interposed therebetween. In the cutting unit 24, the movable blade 241 moves toward the fixed blade 242, and the movable blade 241 and the fixed blade 242 cross each other in a scissors shape, thereby cutting the recording paper S.

In such a printer 1, printing is performed while the recording paper S is pulled out from the roll paper R by rotating the platen 23. Here, when the printer 1 is employed in business equipment, roll paper R having a large winding radius may be used in order to reduce the frequency of replenishment and replacement of the roll paper R and enable long-term use. For example, a roll paper R having a winding radius of 10 inches has a weight of about 4 kg in a new state, and the recording paper S can be pulled out from the roll paper R on the platen 23. Desired.

On the other hand, the performance required for the printer 1 includes an improvement in printing speed. Therefore, a roll paper printer is required to perform printing while quickly pulling out the recording paper S from the roll paper R. Therefore, it is necessary for the platen 23 to pull out the recording paper S from the roll paper R at a speed capable of realizing a desired printing speed. In particular, at the start of printing when the roll paper R is stopped, the drawing speed of the recording paper S is required to reach a desired printing speed within a short time.

In response to such a request, in the supply unit 10 provided in the printer 1 of the present invention, the rotating member 12 is provided.
Therefore, the force required to pull out the recording paper S from the roll paper R is reduced, and the load on the motor connected to the platen 23 is reduced.

FIG. 3 is an explanatory diagram of functions of the supply unit 10 included in the printer 1. In the figure, the state of the roll paper R and the rotating member 12 before the start of printing (before starting) is indicated by a one-dot chain line, and the state of the roll paper R and the rotating member 12 after starting the printing (after starting) is indicated by a two-dot chain line. Show.

When the platen 23 rotates and pulls the recording paper S at the start of printing, a force is applied to the roll paper R in the direction of rotating the roll paper R so that the recording paper S is pulled out. At the same time, the tension due to the platen 23 transmitted to the roll paper R via the recording paper S is transmitted from the roll paper R to the rotating member 12 that supports the roll paper R via the rotating shaft 14 and the bearing portion 15, and the rotating shaft. A force is applied in a direction in which the rotation member 12 is rotated about the center 13.

Then, the roll paper R rotates in the paper feeding direction simultaneously with the rotation member 12, and as a result, even if the recording paper S is not pulled out from the roll paper R, the recording is not delayed by the printing on the thermal head 22. The paper S is transported. Further, while the roll paper R rotates, the roll paper R starts to rotate, and the recording paper S is pulled out from the roll paper R.

When the movement of the recording paper S caused by the rotation of the roll paper R and the movement of the recording paper S caused by the rotation of the roll paper R act in cooperation, the roll paper R starts to be pulled out. The inertial load is reduced, and the conveyance delay of the recording paper S at the start of printing hardly occurs.

Further, the roll paper R is supported by the pair of rotating members 12 through which the rotation shaft 14 is inserted. Therefore, the load of the roll paper R is distributed and applied to the pair of rotating members 12, the load applied to the rotating shaft portion of the rotating member 12 is distributed, and damage to the rotating member 12 can be suppressed. .
The printer 1 having the supply unit 10 of the present embodiment has the above configuration and function.

According to the supply unit 10 configured as described above, a delay in conveyance of the recording paper S at the start of printing is suppressed, and printing defects are less likely to occur at the start of printing.

Moreover, according to the printer 1 having the above-described configuration, since the supply unit 10 as described above is provided, it is possible to suppress printing defects at the start of printing.

In the present embodiment, the print medium is described as the roll paper R. However, the present invention is not limited to this. For example, the print medium is wound in a cylindrical shape such as a strip-shaped cloth or a nonwoven fabric wound in a cylindrical shape. A mechanism for supplying another print medium may be used.

In the present embodiment, the printer 1 is a so-called thermal printer using a thermal coloring method. However, the present invention is not limited to this, and the printer 1 can be applied to a printer employing another printing method such as an ink jet printer or a laser printer. is there.

In the present embodiment, the rotating shaft 14 is provided separately from the rotating member 12, but the present invention is not limited thereto, and the rotating shaft 14 and the rotating member 12 are provided integrally. It is good as well.

Moreover, in this embodiment, although a pair of rotation member 12 was provided in each of the support leg 11, it does not restrict to this. For example, the rotating member 12 is provided only on one support foot 11 and the rotating shaft 14 provided integrally with the rotating member 12 supports the roll paper R in a cantilever manner. There is an effect.

In the present embodiment, the pair of rotating members 12 provided independently on the support legs 11 as the rotating portions have been described. For example, as shown in FIG. It is good also as having the connection member 19 which connects these rotation members 12 mutually. When the pair of rotating members 12 are connected by the connecting member 19, the movement of the pair of rotating members 12 is synchronized.
It becomes possible to rotate the rotating member 12 more easily.

[Second Embodiment]
FIG. 5 is an explanatory diagram of a print medium supply mechanism and a printer according to the second embodiment of the present invention, and is a cross-sectional view corresponding to FIG. 2 of the first embodiment. The print medium supply mechanism of the present embodiment is partially in common with the print medium supply mechanism of the first embodiment. In this embodiment, the same code | symbol is attached | subjected about the component which is common in 1st Embodiment, and detailed description is abbreviate | omitted.

The printer 2 illustrated in FIGS. 5A and 5B includes a supply unit 40 that supports the roll paper R.
The supply unit 40 supports a pair of support legs 41 provided on both sides of the frame 30, a pair of rotation members 42 provided on the support legs 41 facing the roll paper R, and the rotation members 42. Feet 41
A rotation shaft 43 that is connected to and rotatably supported, a rotation shaft 44 that is inserted into the roll paper R and rotatably supports the roll paper R, and a bearing portion that is provided on the rotation member 42 and supports the rotation shaft 44. 45,
have. In addition, a pair of rotation member 42 corresponds to the rotation part of this invention.

The support foot 41, the rotation shaft 43, the rotation shaft 44, and the bearing portion 45 are each the first described above.
Since it is the same structure as the support foot 11, the rotation axis | shaft 13, the rotating shaft 14, and the bearing part 15 which were described in embodiment, description is abbreviate | omitted.

The rotating member 42 includes a first member 421 to which the rotating shaft 43 is connected, a second member 422 that is separated from the first member 421 and provided with a bearing portion 45, and the first member 421 and the second member 422. A connecting shaft 423 and a biasing member 424. Further, the second member 422 is provided such that the distance from the first member 421 can be changed in the extending direction of the connection shaft 423.
The urging member 424 is provided to urge the second member 422 in the direction of the first member 421.

The supply unit 40 having such a rotating member 42 is driven as follows.
First, as shown in FIG. 5A, when a new roll paper R is attached, the second member 422 is provided.
Is a position that sinks downward due to the weight of the roll paper R and balances with the elastic force of the biasing member 424,
Alternatively, the connecting shaft 423 is arranged so as to move to a limit position where it can be separated from the first member 421 in the extending direction of the connecting shaft 423. The roll paper R is disposed away from the rotation shaft 43 as the second member 422 moves. Here, the distance between the rotation shaft 43 and the roll paper R is a separation distance between the rotation shaft 43 and the center of the rotation shaft 44.

On the other hand, as shown in FIG. 5 (b), when the recording paper S is consumed, the winding radius of the roll paper R becomes small and the roll paper R becomes light at the same time. 42
2 is raised. Then, the roll paper R moves along the rotation shaft 4 as the second member 422 moves.
3, the distance between the rotation shaft 43 and the center of the rotation shaft 44 is shortened.

Here, when the remaining amount of the roll paper R decreases, the force (dynamic load) necessary to rotate the roll paper R around the rotation shaft 43 or rotate around the rotation shaft 44 becomes smaller.

On the other hand, even if the remaining amount of roll paper R decreases, the distance between the rotation shaft 43 and the roll paper R is as shown in FIG.
), The torque obtained by pulling by the platen 23 is constant. Then
As the remaining amount of the roll paper R decreases, a relatively large torque is gradually applied to the roll paper R with respect to the force (dynamic load) necessary for the rotation or rotation of the roll paper R. .
As a result, in the printer, the recording paper S is pulled out so much that the recording paper S is easily loosened. Such looseness of the recording paper S causes paper breakage or clogging at the insertion opening A, and may cause printing failure.

On the other hand, according to the supply unit 40 of the present embodiment, when the remaining amount of the roll paper R decreases (when the weight of the roll paper R decreases), the distance between the rotation shaft 43 and the roll paper R (the rotation shaft 43). And rotating shaft 4
4) and the torque obtained by pulling by the platen 23 is reduced.

That is, as the force (dynamic load) required for rotating the roll paper R around the rotation shaft 43 or rotating around the rotation shaft 44 decreases, the torque obtained by pulling by the platen 23 also decreases. Further, an excessively large force is not applied to the roll paper R, and the recording paper S is not easily loosened in the printer.

As a result, when the platen 23 rotates and pulls the recording paper S, as shown in the first embodiment, the recording paper S is moved by the rotation of the roll paper R, and the recording is performed by the rotation of the roll paper R. The movement of the paper S functions in cooperation to reduce the inertia load when starting to pull out the roll paper R, and pull out the recording paper S from the roll paper R without causing a delay in transporting the recording paper S at the start of printing. It becomes possible.

Even with the supply unit 40 configured as described above, the conveyance delay of the recording paper S at the start of printing is suppressed, and printing defects are less likely to occur at the start of printing.

The preferred embodiment of the present invention has been described above with reference to the accompanying drawings.
It goes without saying that the present invention is not limited to such examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

In this example, a printer having a support unit having only a function of supporting roll paper is used as a comparative example, and three types of printers having a print medium supply mechanism of the present invention are used as Examples 1-3.
The load when pulling out the recording paper from the roll paper was measured. In Examples 2 and 3, when the distance between the rotation axis and the center of the roll paper in Example 1 is L, measurement was performed with the rotation axis set at positions 2L and 3L apart from each other. Moreover, in each Example and the comparative example, it measured about 4 types of roll paper from which a winding radius differs.

The results of this example are shown in the graph of FIG. In the graph shown in FIG. 6, the horizontal axis represents the roll paper winding radius, and the vertical axis represents the load (dynamic load) required to pull out the recording paper from the roll paper.

As shown in the figure, in the roll paper of any winding radius, the dynamic load at the time of pulling out was smaller in the example than in the comparative example. For example, in the embodiment, the load required to pull out a roll paper having a winding radius of 10 inches corresponds to the load required to pull out a roll paper having a winding radius of 8 inches in the comparative example.

Moreover, it was found from the comparison between Examples 1 to 3 that the dynamic load increased as the distance between the rotation shaft and the roll paper center decreased. For example, in the state where the distance between the rotation axis and the roll paper center remains the same as that in the third embodiment (3L), the rotation axis and the roll paper center Is gradually shortened from the condition (3L) of the third embodiment (third embodiment: 3L, second embodiment: 2L, first embodiment: L), the fluctuation of the dynamic load becomes small.
This confirmed the usefulness of the present invention.

1 ... printer (printing apparatus), 10 ... supply unit (print medium feeding mechanism), 12 ... rotating member (rotating portion), 13 ... rotating shaft, 14 ... rotary shaft, 19 ... connecting member, 22 ... thermal head (Printing means), 23 ... platen (conveying means), R ... recording paper (printing medium)

Claims (6)

A rotating shaft that is inserted through the winding center of the belt-shaped print medium wound in a cylindrical shape and rotatably supports the print medium;
A rotating part that supports the rotating shaft,
The rotating part is provided to be rotatable around a rotating shaft set at a position parallel to the extending direction of the rotating shaft and different from the extension shaft of the rotating shaft,
The print medium supply mechanism according to claim 1, wherein a separation distance between the rotation shaft and the rotation shaft is shorter as a remaining amount of the print medium is smaller. The rotating unit has a pair of rotating members that sandwich the print medium,
The print medium supply mechanism according to claim 1, wherein the rotation shaft is provided across the pair of rotation members. The rotating unit has a pair of rotating members that sandwich the print medium,
The print medium supply mechanism according to claim 1, wherein the rotating member is capable of supporting the rotating shaft.   The print medium supply mechanism according to claim 2, wherein the rotation unit includes a connection member that connects the pair of rotation members to each other.   5. The print medium supply mechanism according to claim 1, wherein the print medium is roll paper on which a belt-like recording paper is wound. A print medium supply mechanism according to any one of claims 1 to 5,
Conveying means for pulling out and conveying a belt-shaped print medium wound in a cylindrical shape, held by the print medium supply mechanism;
And a printing unit that prints on the drawn print medium.

Images